Database Users

Why Pocket PC generally consumes more battery than others?

I have always wondered why? As the battery issue has constantly become the one embarrasing issue for my Xda II.
Let's compare Xda II and Sony Ericsson P900 ...
Xda II uses LiPolymer 1200mAh, 64k color with 240x320pixels.
Whereas SE P900 uses LiPolymer 1260mAh, 64k color with 208x320pixels.
So, SE P900 has the extra 60mAh, and a wee bitty smaller screen ... but the myth remains that Xda II (or othe Pocket PCs) consumes much more power?? Why is that? Can someone throw some lights why is this so? I would really like to know.

well this is unfair.. comparing xdaII's battery time with something like p900.. hardware specifications are billion years apart :lol:
xdaII has 400mhz processor while p900 has 150mhz(in fact less than that)

I think the official Sony Ericsson score is 156mhz.
Ive owned both a P900 and XDA2, and i think the reason why the XDA consumes more power is because of it being a more powerful unit clockspeed and memory wise, it has a larger better quality screen with a more powerful backlight. The Bluetooth strength is much more powerful reliable ( even though its still 10m ), the speaker is louder, it has a better quality camera and can run more CPU intensive apps which in turn require more battery power.
The XDA2 is always on too, it has no startup like the P900 which is a phone. It has to warm up each time you switch it on. The XDA2 doesnt, it simply flicks on instantly the moment you hit the power button.

dimming the back light setting while on battery to close to the dimmest setting, your battery life will dramatically improve, and the backlight is bright enough in this setting not to make you squint.
I do this all of the time, as I think it is by default too bright anyhow....

One reason why the Pocket PC consumes more power than a regular cell phone is that Pocket PC owners usually use their Pocket PCs more often than regular cell phone owners use their phone. This is because the Pocket PC has a lot more uses than a regular cell phone. We constantly switch on our Pocket PCs to look at our schedule, to check our lists, to listen to music, to watch videos, to read e-books, to play games, to write notes, to surf web sites, to use the calculator, to record voice messages, or simply to look cool. In contrast, regular cell phone owners usually just use their phones to make or answer phone calls and send text messages.

Jargon said:
One reason why the Pocket PC consumes more power than a regular cell phone is that Pocket PC owners usually use their Pocket PCs more often than regular cell phone owners use their phone. This is because the Pocket PC has a lot more uses than a regular cell phone. We constantly switch on our Pocket PCs to look at our schedule, to check our lists, to listen to music, to watch videos, to read e-books, to play games, to write notes, to surf web sites, to use the calculator, to record voice messages, or simply to look cool. In contrast, regular cell phone owners usually just use their phones to make or answer phone calls and send text messages.
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You got a point :wink:

No, I'm comparing Xda II with P900 & Treo 600 (PDA + Phone) whose batteries last much longer than Xda II, not normal phones.
It makes sense that the CPU clockspeed cause the unit to be power hungry. Any indication there will be any battery with higher capacity for the Xda II?

..
The P900 is _not_ a PDA phone, it's a phone 19 year olds buy to look techy. It's a phone first, PDA (if at all) second. XDAs and the like are PDAs first, phone's second. In my opinion, anyway

Yeah, the P900 is a phone with some basic PDA features. The XDA II is a PDA with phone features. Actually, the XDA II is a general-purpose pocket-sized computer. It's even much more powerful and has more total memory and storage space than my first desktop PC (a 33-MHz i486 PC with 4-MB RAM and 130-MB hard disk).

The reason i sold my P900 and got a XDA2 was because i realised it really wasnt a PDA at all - i wanted a PDA. Sorry to all P900 owners, but the P900 is in no way a PDA, its simply a powerful phone with PDA like features - but that doesnt make it a PDA.
Another reason why the XDA2 would use more power than phones is the RAM, more RAM means more power - especially with the XDA2's storage being volatile memory.

I wonder if the new ROM has any new battery management features where it will clock down the processor speed when the device goes to sleep, and clock back up when it's in use ?

I've seen some posts about certain third-party programs (Battery Pack, etc.) that might be draining the battery quickly.

XDA II Battery Life
I have just upgraded to the O2 Asia 1.60WWE ROM, and have found a deterioration in the already short battery life of the XDA II. However, I have a second battery and can live with that limitation. It is a PDA after all.
More significant is the drastic shortening of the battery life of my Bluetooth Headset, a Sony Ericsson HBH-20. I used to get 2 - 3 days of life from it, but after the upgrade I get about 6 hours!! :x
It suspect the Bluetooth in the new ROM is much more active than the earlier 1.52 version and this constant querying of the headset by the phone shortens its life. I can't have a spare battery for the headset, so it is a right proper pain.
I have tried the headset with another BT phone, and I still get 3 days so it is not a dead headset battery.
Anyone else find this problem??
PS Towa's latest BT Tools can't help as in the auto power down mode the headset refuses to wake up when a call is received.

XDA II Battery Life
I have just upgraded to the O2 Asia 1.60WWE ROM, and have found a deterioration in the already short battery life of the XDA II. However, I have a second battery and can live with that limitation. It is a PDA after all.
More significant is the drastic shortening of the battery life of my Bluetooth Headset, a Sony Ericsson HBH-20. I used to get 2 - 3 days of life from it, but after the upgrade I get about 6 hours!! :x
It suspect the Bluetooth in the new ROM is much more active than the earlier 1.52 version and this constant querying of the headset by the phone shortens its life. I can't have a spare battery for the headset, so it is a right proper pain.
I have tried the headset with another BT phone, and I still get 3 days so it is not a dead headset battery.
Anyone else find this problem??
PS Towa's latest BT Tools can't help as in the auto power down mode the headset refuses to wake up when a call is received.

Prophet's battery is dreadful...

Hey guys, I'm satisfied with almost every aspect of the prophet, except battery time...
I mean in suspend the battery is great. But what if you want to do any real work on the prophet? This is what I get:
Screen off, Wifi on (useful for skype, IMs etc.)
3.45 hrs from full charge
Screen on, all else off (word processing, games etc.)
3.50 hrs from full charge
Screen on, Wifi on (email, internet)
3.40 hrs from full charge
Now tell me if this is not too little?
This is off course with normal battery.

You could set your screen to the lowest brightness that you can use also set the wifi to its lowest power setting these 2 functiions are the biggest users of power in my view

Radio ON, Wifi OFF, Screen backlight at level 2 or 3 (when outside). Some data connections, few Wifi cnx too (then turned OFF), 1 or 2 syncs using Bluetooth and my SPV M600 battery runs about 5Hrs according to my "upmeter" ( free at http://ae.inc.ru )
You can buy on Ebay a 1800mah bat. (50% more power than the original bat.)

just curious,
do u have phm traylaunch enabled ?
mine sux the juice out of my prophet whenever I enabled the traylaunch..

Is that 1800 mAh battery with extended thickness? if not it might be worth it.
I dont use phm tray launcher. But wifi and display are on quite frequently.

farbird said:
just curious,
do u have phm traylaunch enabled ?
mine sux the juice out of my prophet whenever I enabled the traylaunch..
Click to expand...
Click to collapse
I do have PHM TrayLaunch installed but did not notice faster battery drain. Is this something you just experienced or did anyone else comment about this problem?

Battery is way shorter in the Prophet than in any other device i've had before. Same usage of course.
I could live with this limit, but can not stand with some other wm5 imposse on us, such as max size on contact notes field, or the inability to sync via BT.
Am I the only one missing my trusted JAM?

I am not sure its shorter than in other devices of similar features, but I do know for me its not enough. I think the Jam would actually be way shorter with Xscale over omap processor. So no, i would not say you've made the wrong choice.
Not sure what you mean about no synching over BT? It should work fine!
BTW, anyone know about this 1800mAh battery on ebay that apparently does not increase thickness?

try this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=9720781998

krale said:
I am not sure its shorter than in other devices of similar features, but I do know for me its not enough. I think the Jam would actually be way shorter with Xscale over omap processor. So no, i would not say you've made the wrong choice.
Not sure what you mean about no synching over BT? It should work fine!
BTW, anyone know about this 1800mAh battery on ebay that apparently does not increase thickness?
Click to expand...
Click to collapse
Thanks for your comment.
IMHO battery life IS shorter, as a matter of fact. I know about the OMAP, but it takes two of them, so.....
BT syncing simply does not work. Maybe it's a matter of XP-WM5 combination, but fact is that my prophet "does not find a PC with the active Sync service" Any help on that?
I've been able to get TomTom 5 to work, pair with several headsets and handsfree devices, but no way around the Active Sync issue, no matter what the COM ports or tricks I've tried. I even changed BT drivers from Widcomm to MS in my notebook, same result.
I haven't read about the large capacity battery, but if this is going to be "oversized" or make it heavier, I'd rather would take an extra USB cable around the office or my notebook.

krale said:
I am not sure its shorter than in other devices of similar features, but I do know for me its not enough. I think the Jam would actually be way shorter with Xscale over omap processor. So no, i would not say you've made the wrong choice.
Not sure what you mean about no synching over BT? It should work fine!
BTW, anyone know about this 1800mAh battery on ebay that apparently does not increase thickness?
Click to expand...
Click to collapse
Thanks for your comment.
IMHO battery life IS shorter, as a matter of fact. I know about the OMAP, but it takes two of them, so.....
BT syncing simply does not work. Maybe it's a matter of XP-WM5 combination, but fact is that my prophet "does not find a PC with the active Sync service" Any help on that?
I've been able to get TomTom 5 to work, pair with several headsets and handsfree devices, but no way around the Active Sync issue, no matter what the COM ports or tricks I've tried. I even changed BT drivers from Widcomm to MS in my notebook, same result.
I haven't read about the large capacity battery, but if this is going to be "oversized" or make it heavier, I rather would take an extra USB cable around the office or my notebook.

Well just to let the curious know, I received the 1800 mah battery, the one also priced on ebay, with NO thickness increase, and I cannot believe it...
It just keeps going and going and going. I did the same tests as above, and could not get it to run out.
Wifi on (all else off) lasted for about five hours and was still arround 68%
Screen on all else off lasted for about 6 hours from an 85% charge and it was still on 39%...
I mean I know the math 1800 is 50% more than 1200, but I seem to be getting A LOT more than 50%. Any explanations?

Sync via Bluetooth is perfectly working for me.
You have to create a BlueTooth Com Port from your PC. Just follow instructions in ActiveSync Help File.
I can listen to mp3 for more than 4hours with screen off... and with a BlueTooth Headset... Maybe it's draining less power coz it just sends the signal and doesn't have to use external speakers...
hum... the 1800mh battery seems great... is it really good quality ?

I will keep you posted as I keep testing it in the next few days, but so far I'm impressed.
The maker is the same as the original battery (DynaPack) so quality is the same.

The battery is shorter because the phone is always registering on the GSM network.
It has some kind of bug in it.
You can check this by going to Settings > Phone > Network and check that the current network is sometimes flashing "home service" instead of the name of the operator.

rjtd said:
The battery is shorter because the phone is always registering on the GSM network.
It has some kind of bug in it.
You can check this by going to Settings > Phone > Network and check that the current network is sometimes flashing "home service" instead of the name of the operator.
Click to expand...
Click to collapse
As in manual not automatic.

CookieKid said:
As in manual not automatic.
Click to expand...
Click to collapse
Manual or automatic, it gives the same "****".
http://www.youtube.com/watch?v=UKO1xaY1z7Q

http://cgi.ebay.co.uk/ws/eBayISAPI....092516258&fromMakeTrack=true#ebayphotohosting
anyone seen 2500mah ? I'm trying to find out if it bigger.

2500mah? seems kinda fake to me if it is the same size and thickness as a 1200mah or 1800mah battery.
The 1800mah extended battery is possible because they removed the hard plastic cover on top of the battery so they can fit a slight bigger capacity battery.

these 1800mah batteries (says not dynopack on ad, just chinese copy!) are they much heavier, i have just ordered one, bit concerned they may actually be lithium ion (not lithium polymer)

New power consumption tests (incl. HTC Wizard and Universal)

New power consumption tests (Dell x51v, HP hx4700, PLoox720,HTC Universal and Wizard)
I’ve constantly been receiving requests (see for example this thread) to publish more and more power consumption measurements of current Pocket PC devices. Here you are
First, please read at least this article (if you haven’t already done so) to understand what this article is all about. I also highly recommend the other articles I’ve linked in from the Recommended links section.
HTC Wizard (a.k.a. imate K-Jam, T-Mobile MDA Vario, Qtek 9100, MDA Vario, XDA mini S, SPV M3000, VPA Compact II, Dopod 838) radio power consumption
As promised, I’ve run some long-lasting tests to find out more about the power consumption of the radio unit itself. It’s about 7.5% a day (I’ve measured it for two days; not counting in the ~2.5%/day battery life depletion needed to refresh the dynamic RAM memory) in inactive (no SIM is inserted but the radio is online and is ready to initiate emergency calls) mode. Again and again, these figures, along with the ~9% (there, not counting in the ~2%/day RAM refreshing-related depletion either) of Universal, are relative (show how the power consumption of these devices’ radio compares) and only show how they fare at a given geographical location. That is, they can ONLY be used to compare each device’s being power-hungry, NOT as an absolute result as “your device will consume that much power a day in YOUR home”.
Wizard’s 7.5% a day is an excellent result and is slightly better than the ~9% of Universal, particularly taken into account the bigger battery size of the latter.
Standard power consumption test suite: now, for the Universal and the hx4700!
I’ve also re-run my standard test suite including the HTC Universal (a.k.a. i-mate JasJar, Qtek 9000, O2 XDA Exec, SPV M5000, MDA IV/Pro) and the HP iPAQ hx4700 (with WM5 version 2.01 – see FAQ here on this particular ROM version) now to find out how they behave.
The test suite I’ve tested:
Backlight tests: (all with no wireless units (GSM radio, Bluetooth, Wi-Fi, IrDA) switched on, no CPU usage. This finds out the absolute minimum power your device at least will consume when it’s switched on, runs at the default (automatic) CPU speed.)
No backlight at all (Note that in this scenario these devices are far from being usable, particularly the Axim x51v, which has an, in my opinion, slightly less visible screen in external light than the other three devices (which all have a screen using the same Sony technology and, therefore, behaving in a very similar fashion)
(Absolutely) minimal backlight
Maximal backlight (may be useful to know for example when watching videos on Sony screens because of the very high contrast and saturation of these screens (the x51v's not-really-saturated, not-contrasty screen has a definite advantage here) or in outdoor circumstances when you need to use the maximal backlight level available to see anything)
Wi-Fi searching for networks (also testing possible power saving modes to find out whether they’re of any help)
CPU usage vs. power consumption tests with Resco Audio Recorder (recording in q:3 32 kHz 19 kbps Speex mode (my favourite one with the best size/quality ratio but, unfortunately, with pretty high, about 60% CPU usage) - please see Everything you may need to know about sound recording on the Pocket PC for more information.)
Note that, this time, I’m also stating the original charge level at the start of the test. As is also stated for example in this pretty nice article by Brighthand forum member tanbam, there may be slight (not much) differences in power usage depending on the charge level of the battery because of the proportional Voltage level decrease as the battery is discharged. (Note that the Voltage decrease with Li-Ion batteries is in no way as visible as with other kinds of batteries. That is, a Li-Ion battery that only holds little charge will still have only a bit less Voltage than a battery full of charge. This is why there aren’t major differences in the low-charge and the fully-charged cases, Amperage-wise).
As can clearly be seen, what I’ve stated in my first battery consumption-related articles and tests is still topical:
when there is some remarkable CPU usage (see the Resco test), the power consumption figures skyrocket, particularly with the iPAQ and the x51v, particularly because both are 624 MHz devices, as opposed to the 520 MHz Universal and the PL720 (the latter consume decidedly less power in these cases). It’s, therefore, essential that you use some kind of CPU underclocking, especially on 624 MHz devices, when you run an application that constantly uses the CPU.
Fortunately, CPU underclocking is already supported by the x51v (in the Processor tab in the Settings/System/Power applet) but, unfortunately, not in the hx4700. Note that the Resco results are almost the same in the 624 and the 520 MHz modes; it’s only in a heavily (on the verge of usability underclocked) 208 MHz case that it’s visible decreasing. The case is a bit different with games – please see my former articles on the power consumption of the x51v and on my remark on what applications / games run OK when you (radically) underclock the device.
the Pocket Loox 720 is by far the best device, power consumption-wise
the lowest backlight level (with the – this is very important! – automatic backlight mode enabled as can be seen in here – it’s not enabled by default!) with the hx4700 consumes very little, as opposed to the other devices
when idling (without backlight – again, the hx4700’s backlight is far more battery-friendly than that of the other devices when used sparingly), the PL720 consumes the less; then comes the Universal, the x51v and, finally, the worst-behaving hx4700.
the various Wi-Fi power saving modes aren’t worth anything (at least when the device is actively searching for networks). In Wi-Fi, it’s again the PL720 that turns out the most power-saving (in my personal tests, it consumes about 25% an hour with BT enabled – connected to a StowAway BT keyboard -, in Web browsing mode, with the lowest backlight and connected to a Wi-Fi network).
BT and IrDA: Note that the chart doesn’t contain Bluetooth and IrDA beam activation power consumption data because I’ve already published them all. In a nutshell: you can freely activate and, with Bluetooth, actively use them (it’ll only result in an additional 1-2 mA power consumption, except on the PL720 in BT PAN mode, where you have taken into account what I’ve stated here), except for the hx4700, where it adds another 80-90 mA power consumption.)
finally, the Universal has turned out to be pretty good surprise: I’ve expected far worse, based on real-life usage. (Read: I need to recharge it on a daily basis with even moderate Web browsing – no hard-core gaming or stuff at all! – and mail reading while, using it in entirely the same way, the HTC Wizard doesn’t need recharging for days. Compared to the Wizard, it really sucks battery life-wise; compared to other VGA devices, it fares pretty well.) It fares decidedly better than the x51v and the hx4700 in almost every respect, particularly in the CPU usage and the Wi-Fi tests.
The comparison / result chart is available here (CLICK THE LINK!)
(All values are given in milliAmpers (mA).)
Recommended links
Maximize Battery Life by Minimizing Power Consumption!
Extend your battery life – never before published tips and comparative benchmarks!
Power consumption measurements of the HTC Universal (a.k.a. i-mate JasJar, Qtek 9000, O2 XDA Exec, SPV M5000, MDA IV/Pro)
Further power consumption tests on the HTC Wizard
Ever wanted to know how much power your HP iPAQ hx4700’s wireless units consume? Here’s what you’ve been waiting for. Also, a VERY BAD BUG discovered in the WM5 2.01 hx4700 BT module!
Updates to the “Windows Mobile Team on the Power Consumption issues of Pocket PC's; new power consumption measurements published!” articles – first long-lasting power consumption measurement results on the HTC Wizard
Windows Mobile Team on the Power Consumption issues of Pocket PC's; new power consumption measurements published!

[REF] Leo power consumption breakdown

With the HD2's pretty short battery life compared to my previous HTC phones, and also as I was a bit bored , I decided to have a look at how much the different systems drain in the HD2, and did some tests.
So for anyone interested, here are the results:
Base consumptions: (pick the one that suits your situation)
Standby, phone on, WIFI+BT off, no connections active: 5mA
Processor running idle, screen off, connections as above: 55mA
100% CPU usage (Coreplayer benchmark), connections as above: 315mA
USB connected, connections as above: 125mA
Additions: (add this to the base one depending on what you have on)
Connections:
BT on, idle: +1mA
Wifi on, idle: +5mA BUT!! If you enable wifi during standby (with BsB Tweaks or the WifiNoStandby CAB), the processor does NOT go to standby
anymore, so the base needs to be the 55mA above!
Connected to EDGE, idle: not measureable
Connected to 3G, idle: +4mA
Beware those 2 will occasionally and unpredictably send data every now and then, so this doesn't necessarily mean much.
BT transfer (file copy through ActiveSync, 120kB/s, CPU usage ~2%): +80mA
Wifi transfer (file copy with Wifi Remote access, 1MB/s, CPU usage ~3%): +200mA
EDGE/3G transfer: Pretty impossible to measure due to so many variables, but can be extreme (total current consumptions of 850-1150mA, so very approximative 500-800mA draw from the data connection during page loads are common!), and leads to most of the energy draw when using the net a lot. EDGE uses more power than 3G, consumption is higher when network coverage is lower, bad network throughput or congestion also mean lots of retries/overhead and less effective data transfer, using power for a longer time until the data is finally there.
Memory access (large file transfer):
Internal read/write through ActiveSync (speeds 2.5 / 2.1 MB/s respectively): +20mA / +130mA
Card read/write through ActiveSync (speeds 3.2 / 2.7MB/s respectively): +25mA / +40mA
Card read/write in USB disk mode (speeds 7.5 / 5MB/s respectively): +40mA / +45mA
Backlight:
10%: +65mA
20%: +78mA
30%: +90mA
40%: +105mA
50%: +121mA
60%: +136mA
70%: +154mA
80%: +170mA
90%: +190mA
100%:+210mA
GPS:
+95mA
Flashlight (with HTC Flashlight):
Level 1: +32mA
Level 2 (same as camera flash on): +107mA
Level 3 (same as camera "bright flash during shot"): +530mA
And remember the battery capacity: 1230mAh
So with this you can calculate your battery life for various activities. For example:
- Playing a video with full backlight: Let's say the video is well encoded (30% CPU use, for example 720x400 1Mbps DivX), that's about 150mA base, + 210mA backlight = 360mA, resulting in about 3h20 battery life.
- Same at night with only 40% backlight: Life goes up to about 5h!
- Wifi during standby for an 8h night, or a program that somehow prevents the phone from entering standby: 60mA or 55mA respectively, draining about 40% of the battery during that time.
- GPS program, with 70% backlight: Let's assume 150mA for the processor as it has some work to do, 90mA for the GPS, 154mA for the backlight = 394mA, or 3 hours.
- Music through wired headphones, screen off: the 55mA base plus a little 5mA as MP3 decoding is nothing for the CPU = 60mA or 20h.
- Same with a BT headset, with about half the BT bandwidth: 60+40 = 100mA or 12h
etc.
Charging
[EDIT 14.04.10]
This is now a dedicated section as I did some more thorough charging tests.
So, as some of you might know, the HD2 has 2 charging "modes".
- One is USB, that is used if the phone is connected to a PC, or an unknown device. In this mode, the current the HD2 will draw from the port/charger is limited to approx. 470mA, to stay within the maximum of 500mA a USB port can supply.
- The other is "dedicated charger", which is recognised on the original HTC charger (and some others, it's becoming a standard for a "dedicated charging USB port") by shorting of the 2 data pins of the USB connector in the charger.
USB charge
Important to know, during USB charge, the phone will NOT go to sleep, as it's supposed to be connected to a PC, and be running either ActiveSync, Disk drive mode, or modem, and in all 3 cases would be expected not to shutdown. So not only the current supplied to the HD2 is low, but the phone draws some of it for itself, leaving very little for actual charge - so expect loooong charge times.
USB charge with screen on (backlight dimmed, 10%): 285mA
USB charge with screen off (standby): 345mA (which shows the processor still runs and draws the "base USB" current)
Dedicated charger
When used with a charger that has the 2 USB data pins shorted, such as the original charger, the HD2 will draw a current that is proportional to the voltage on the USB power lines. To measure this I have used the original supplied USB cable, a variable regulated power supply, USB socket (with data pins shorted), and 2 meters for voltage/current. Voltages are measured at the "PC" end of the USB cable, so not taking account of losses in the USB cable. Will talk more about this later on.
Current vs Voltage diagrams are attached. Charge current is proportional to voltage, linearly until it reaches the max charge current, approx 830mA. This was measured so that the only draw is charge. If the phone is turned on while at max charge current, it will draw extra, until it reaches about 980mA, and will then stop to respect the 1A rating of the stock charger.
Now, to the influence of USB cables. I initially had some trouble with inconsistant numbers, phone only drawing 670mA from the stock charger, i.e matching neither the ~350mA from USB, or ~830mA from stock charger in "normal" condition. Turns out that to make it more convenient on my workplace I was using an USB extension between charger and HD2 cable. It was a $2 extension I bought on Dealextreme. Removing it solved the problem... and after making those measurements I poked with it again. Turns out that at 1A current, the voltage drop in the extension (which by the way isn't longer than the HD2's USB cable) was 1.8V! Yep, nearly 2 Ohms for a 1.5m extension! Couldn't believe it.
I have a cheap Chinese microUSB cable that wasn't as bad,but still significantly more resistive than the stock one, hence me noting I used the stock cable for my tests. So, quality of the cables, extensions, adapters IS important! Note the phone correctly reaches full charge current a little bit under the 5V USB spec, so everything is well tuned.
Now, important to know, Most 3rd party chargers will not have the 2 USB data pins shorted, and will thus result in the same behavior as mentioned under USB charge, the processor will also be running continuously drawing the "base USB" current.
It is often possible to modify 3rd party chargers by opening them and shorting the pins, speeding up charge. The voltage/current curve behavior is actually helping there, because thanks to it if the charger is overloaded its voltage will most likely fall a bit, and the HD2 will thus draw less and find a nice balance point. This DOES NOT mean there's no possiblilty of damaging the charger, but all 3 I modified did well. One that was really weak resulted in not much more current being drawn after the mod than before (i.e voltage fell very low, approx. 4.4V), however the gain from not having the processor running like in USB mode still sped up charge a little.

Thank you, that is one useful chunk of comprehensive information
Could you please explain the exact measuring method for these tests?
40% backlight at night is a tough example tho, Lumos on my device is set to 10% for 0 sensor value, and only because I can't set it to lower than 10%... nice to know battery drain goes up twice from 10% to 60%!
Also, 100% is usually really necessary under direct sunlight, in a normal lit room probably 40% backlight is more than enough to watch a video... all in all, with your superinteresting info, the battery doesn't look like lasting "too short" now, but more or less "the right amount considering the battery capacity".
My iPaq 210 has a 2200mAh battery, just to make a comparison... that's why I could go for 8 hrs during some bus trips while watching tv series, and I just needed to swap battery and used a little of the second one.

What's your estimate of the drain caused by activating push email? I've recently been doing some rather crude experiments myself, and one provisional conclusion is that push email on a hotmail account uses a lot more battery than push email on an Exchange server.

Excellent stuff, you are to be congratulated.
I have a long held theory and I wonder if you are in a position to to test it?
I believe that battery consumption is greatly increased when an app is run from mem card and would be intrigued to see a comparison between an install to this as opposed to phone mem.
Any chance?

Battery levels
I found that power consumption of the battery got even worse after I went to Rom 1.66.707.1. However, after a few days, I let it run all the way out, switched back on, it ran out after a few minutes. Then after an overnight charge I found the battery (on standby) only went down by about 10 -12 % in 24hrs. I'm hoping this performance will continue.

What did you use for the testing?

pa49 said:
Excellent stuff, you are to be congratulated.
I have a long held theory and I wonder if you are in a position to to test it?
I believe that battery consumption is greatly increased when an app is run from mem card and would be intrigued to see a comparison between an install to this as opposed to phone mem.
Any chance?
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Click to collapse
That would be reasonable as reading from an external media will need energy to access its contents... still, once the app files have been loaded into the device's RAM, it shouldn't matter much
You could also test by comparing:
1) copy say 30mb from one location to another of the internal mem
2) copy from microsd to microsd
3) copy from mem to microsd
4) copy from microsd to mem

ephestione said:
Could you please explain the exact measuring method for these tests?
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Simply using the built-in current sensor, getting the reads from AEBPlus battery information screen, and methodically turning things on/off once the others are evaluated and can be subtracted from the total reading.
ephestione said:
40% backlight at night is a tough example tho, Lumos on my device is set to 10% for 0 sensor value, and only because I can't set it to lower than 10%...
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Really? You should force the backlight off then
I love bright images myself, so even in my bed in total darkness if I watch a video or photos I'll force 100% backlight I have Lumos set to force 100% for Coreplayer, Resco Photo manager and HTC album
Of course not for browsing or just messing around, in that case it's 20% for me
Shasarak said:
What's your estimate of the drain caused by activating push email? I've recently been doing some rather crude experiments myself, and one provisional conclusion is that push email on a hotmail account uses a lot more battery than push email on an Exchange server.
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That's one thing I'd have no idea about... I've never used push email at all. And that's "standby usage", so hard to evaluate, as you never know when it kicks in.
Measuring that would need to be done on a long time. I'd say to leave your phone one night with push email off, one night with Exchange only, and one night with hotmail only, and then check the difference, preferably with a battery at about 80% charge at the start (mine seems to fall from 100% to 90% in a few minutes before becoming more regular, so I'd say the top of the scale isn't that reliable).
And I should really try push email once, that would be nice, but I *think* I have no provider that can do it for me... well I have a gmail account I never use, I should try to see if I can have it check my usual 3 mail accounts, aggregate and push... never really looked into that stuff.
pa49 said:
Excellent stuff, you are to be congratulated.
I have a long held theory and I wonder if you are in a position to to test it?
I believe that battery consumption is greatly increased when an app is run from mem card and would be intrigued to see a comparison between an install to this as opposed to phone mem.
Any chance?
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Thanks
Well I'd tend to refute that theory, because when I tested the BT and Wifi in use I tried read from internal memory, write to internal, read from card and write to card, and all 4 were identical. I should have mentioned it indeed, but I was mostly interested to seeing if reads (wifi/BT "sending") and writes (wifi/BT "receiving") would have an influence on consumption, which wasn't the case, as well as whether the throughput was different, which wasn't the case either.
But I've done a few more tests, see the updated first post
One intersting thing is firstly that when the HD2 is connected to USB, the current draw grows significantly, so I've made a new "base consumption".
Next, the card is actually faster than the internal memory both in reads and in writes, tested both through activesync for consistency. Writing to the internal memory eats a LOT more than writing to the card. Reading from the card eats a little more than reading from internal memory, probably evens out as the reads are shorter due to faster transfer rate.
I've added some charging tests as well. Apparently, even if the phone "disconnects" from USB when turned off, the processor still runs and uses about the "USB connected" base current.

kilrah said:
Simply using the built-in current sensor, getting the reads from AEBPlus battery information screen, and methodically turning things on/off once the others are evaluated and can be subtracted from the total reading.
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d'oh aebplus has a battery information screen, checking it right away In that case you'd have to take into consideration aebplus' current absorption anyway... which is not measurable as you cannot check the current intake of aebplus without aebplus being running
I have the cab on the sd already, but didn't install if after noticing that didn't work for button assignments with later versions of the rom... does it work for you on that side? I used the program all the time on my previous ipaq because it was oh so useful but never got around to notice it had a battery info subsection.
Really? You should force the backlight off then
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Wouldn't have much sense doing it in the dark would it (admitting it's possible altogether on the HD2!)
But I actually used my oooold casio cassiopeia, about 7 years ago, with backlight turned off, while reading ebooks with speed reader plus during train trips, as the neon lights created a reflection good enough on the display so that I didn't need backlight...
in the end, the backlight died altogether and until I bought a new device, I managed to use it with light turned off

A flashing LED (incoming SMS warning, e.g.) seems to add consumption of 1-3mA.
Running FlexMail in background with a push service (IMAP IDLE) adds up to 30mA.

ephestione said:
does it work for you on that side?
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AEBPlus works fine for me yes... but I don't have a "latest version" ROM AFAIK. I don't like WM6.5.x new softkey arrangement, so I'm staying with 6.5.
Anyway more about Push, I configured that through gmail yesterday, and it works just fine. I left it on during the night, and this morning I had lost 8% battery. So it's pretty much negligible. I received 2 e-mails during the night and was on 3G network.

this is a nice topic! i am interested in how much extra it uses when you are playing a MP3 with the build in HTC app?
maybe it would be a nice idea to make a program that outputs results like you pasted fast and easy (something like a benchmark app) so we can test different rom's fast? too bad i cant write anything otherwise i would try..

OK, seems MP3 uses 120mA screen off, both with Sense player and Coreplayer, so:
Processor running idle, screen off base + 65mA
But it seems to make some pretty big "jumps" once in a while. Maybe they both decode ior fetch from memory by "batches"...

my test,
HD2 rom 1.66
with BT on and BT off (configured but no connection to headset) difference in consumption is 60mA .!
BT is draining my HD2 .!
kilrah said:
OK, seems MP3 uses 120mA screen off, both with Sense player and Coreplayer, so:
Processor running idle, screen off base + 65mA
But it seems to make some pretty big "jumps" once in a while. Maybe they both decode ior fetch from memory by "batches"...
Click to expand...
Click to collapse

OK, I can't confirm the BT issue. Did you observe over a long period of time? The "quiet" current for MP3 I seem to get is 185mA with screen on and backlight at 10%, but sometimes it will climb to 280-320mA for a moment and go down again, both with BT on and off. With screen off for a while it seems to stabilise at the "quiet" level.
BTW, it seems that Advanced task manager isn't reporting CPU usage levels properly. Does someone know of a CPU monitor that works correclty on the HD2?

Yup. review over multiple 6 mins. all baseline(3g/brightness) setting the same. resetting each time for off on BT.
kilrah said:
OK, I can't confirm the BT issue. Did you observe over a long period of time? The "quiet" current for MP3 I seem to get is 185mA with screen on and backlight at 10%, but sometimes it will climb to 280-320mA for a moment and go down again, both with BT on and off. With screen off for a while it seems to stabilise at the "quiet" level.
BTW, it seems that Advanced task manager isn't reporting CPU usage levels properly. Does someone know of a CPU monitor that works correclty on the HD2?
Click to expand...
Click to collapse

Another consideration:
Data connection sucks power when used actively. Badly. As mentioned in the OP I haven't made comprehensive tests due to low monthly allowance, but I've had a look during normal use.
I'm pretty regularly doing 1hr train rides, during which I will be listnening to music , and browse the net at the same time. It's usually bright, so backlight will probably be at 70%. Signal is relatively low most of the time, on EDGE, inbetween small towns. When I'm on a "static" page (reading an already loaded page), current drain varies between 250 and 350mA.
But while loading a page, it will easily soar to 800mA+. Considering it takes 30-60 seconds to read a page, 20 to load a new one, and repeat... you can quickly see that this kind of usage leads to serious drain... in less than 2 hours the battery would be dead.
So be aware of how much power data connection will use. It's directly proportional to the amount of transferred data, and the worse the reception the more power it uses.
I should try using opera mini again, like I was always doing on my Kaiser. I never noticed excessive drain with it, but opera mini easily divides traffic by a factor of 10...

Just wanted to report that the new version of the superuseful BattClock has now a builtin battery current output, even if it's not really update once per second... seems more like one every 10 seconds.
I get ~240mA playing fullscreen stretched Frasier in lowest backlight (but that's with the keypad leds turned on all the time, I don't know why they don't go off, and I don't have keypadledcontrol installed... so that's a problem), and I get a total 630mA with HTC flashlight at maximum.

Good news! Bye bye Batti
Normal about the refresh time, the sensor only updates every 20 secs or so.
Some new considerations I posted somewhere else but should have put here.
After some time the HD2 seems to have better battery life, but usually it's not your battery lasting longer, it's just you not spending your day playing with the thing anymore.
It's always the same thing, the more a device can do, the more you do with it. On my first 1h train journeys after getting my HD2, I was able to kill 50% battery in 1hr. My first thought was "wow, with my Kaiser I would only use like 15%!!"
But then I took a second thought. I used 50%, but I was browsing the web, in bad reception areas, while listening to music the whole time. With my Kaiser, I'd put music on, check 3 webpages, then put it on the tray with just MSN connected and just pick it up to read/type a message once in a while.
On a next trip, I "forced myself" to do the same with the HD2. Just checked the news for 5 mins, then only listened to music and picked up msn once in a while, plus an unexpected 10min phone call. Guess what? I've only used 20% battery during the trip this time
The "problem" is that browsing with the Kaiser was just painful, so I'd just check the news and put it away. On the HD2 it's so comfortable I forget it and just spend my whole trip browsing heavy pages, which obviously kills battery in no time...

exactly my thoughts and findings

Reducing processor frequency - to save power

Hi guys,
If I remember correctly, in the previous WM versions there were options to change the speed of the CPU and that way to save the power and reduce battery consumption?
I am preparing for long, few days GPS assisted hikings and would like to minize the power comsuption of my HTC HD2.
Maybe there good apps for that too?
Thanks.

It already does that automatically.
Consumption of a GPS app like GPS Tuner with screen off is already very low, giving about 8hrs battery life (if you don't do anything else, of course).