[Samsung Infuse 4G] electricpete1:
(I intended to post this in "general:, not q&a)

SUMMARY: I have been slowly decreasing my voltage. Wednesday, three weird things happened on my phone that never happened before (wakelocks, unintended reboot, instant drop in battery indication).

CONCLUSION: I attribute all three things (wakelocks, reboot, instant drop in battery indication) to reaching an unstable voltage.

DESIRED OUTCOMES (Why am I posting this):

1 - I think I understand what happened, but maybe you guys can point out if I'm mistaken.

2 - Maybe someone else will be interested in seeing voltage limits for my phone (-75mV appears to work, -100mV appears to be too low for me... I guess other Infuses may act differently)

3 - It seems to me that maybe excess UV should be considered when investigating causes of wakelocks (there are many other causes of course). This conclusion is based only on this one experience as reported below. I have heard obviously unintended reboot can be associated with too much UV'ing, but I never heard wakelocks could be associated with UVing. Open to comments.

DETAILS:

I’m using stock GB, rooted, Zen’s Infusion A/1600 kernel, with governor conservative 100-1200millivolts.

I have been decreasing my voltage settings by 25 millivolts every other day over the last week.

Wednesday, I got to 100 millivolts below max on all points (except 1600Mhz, which was 50 millivolts down)

Specifically, my levels on Wednesday were:

100 Mhz: 950mv max – 100mv = 850 millivolts

200 Mhz: 950mv max – 100mv= 850 millivolts

400 Mhz: 1050mv max – 100mv = 950 millivolts

800 Mhz: 1200mv max – 100mv = 1100 millivolts

1200 Mhz: 1275mv max – 100mv = 1175 millivolts

1600 Mhz: 1400mv max – 50mv = 1350 millivolts

Before Wednesday, I had performed stability test (using “stability test” program for about 30 minutes... it sweeps the frequencies I think) at 1600Mhz Fmax while 50 millivolts down and another stability test at 1200 Fmax while 75 millivolts down, both for around 20 minutes, no problems there and no other problems with my phone in the last week since I upgraded to GB. When I decreased to 100 millivolts down I only did a 30-second “stress test” from within setcpu at 1200Mhz. No problems there.

All day Wednesday I was running the conservative governor, with Fmin=100 and Fmax = 1200, cfq io scheduler, UV settings as above (all 100 down except 1600Mhz). I have one setcpu profile that puts the phone to 1600Mhz Fmax when I manually launch "Memento Database" program, but I did not launch that program at all on Wednesday, so I never got above 1200Mhz on Wednesday.

My battery profile for the day Wednesday is shown in attached graphic.

The label “phone awake with screen off” points to a time period approx 2-4pm when my phone was awake with the screen off. I have never seen this happen on my phone before, and I look at this screen pretty regularly.

I used the phone heavily during my hour-long ride home from work from 5pm to 6pm (no problems). I was surfing the internet, reading the news about the Hurricane in New Orleans (not tweaking my phone). Phone worked absolutely perfectly throughout this hour long heavy usage.

First thing on getting home, I connected to wifi and surfed for about 5 minutes. At about 6:10pm, while surfing with my battery level happened to be 47% (as I deduced later), suddenly appeared the black screen with Samsung logo ... phone booted up to normal home screen. I think that’s what you guys call the “screen of death”?

I assume the phone reboot may be my first indication that I’ve reached my limit for UV’ing?

But here’s what concerned me more than the SOD:

Immediately after rebooting, my battery now showed 8% !

How does it go from 47% to 8% that fast? I have several screens from “battery monitor widget” and from the Android battery screen, and they all confirm the battery dropped from 47% to 8% over this very short time period (less than 5 minutes). I also have audible low-battery warnings on my phone (generated by Tasker, a lass with a pretty British lady voice) at levels of 40%, then 30%, then 20%, then 10%. I didn’t get any of those audible warnings prior to this spurious reboot – seems to confirm either this was a real drop in battery, or else my battery signal feeding all my applications (battery monitor widget, Tasker, GB battery profile) somehow went bezerk.

I have a hard time imagining this could be a real drop in battery ....where would the energy go? The phone did not get hot.

Is it possible somehow the phone’s battery calibration got confused?

Attached is a screenshot of battery drop.

The rapid drop from 70% to 50% was when I was using the phone heavily for an hour... I consider that normal.

The vertical drop from 47% to 8% is what is completely unexplainable to me. Although I have seen in the forum reports of battery gage reading unreliably in certain circumstances.

By the way, I put my UV setting back to -75 Wed night, and phone working fine ever since. No wakelocks or other anomolies.

Questions:

1 – Is this what is known as “screen of death”

2 – Has anyone seen that type of rapid battery level decrease?

3 – What do you think caused it.... calibration problem or actual loss of battery? If calibration problem, it’s kind of weird that the voltage increased smoothly during recharge afterwards?

4 – Do you think the phone-awake-with-screen off occurences earlier in the day are related to my UV'ing? I didn't see them before and I haven't seen them since went back to -75mV, suggesting they are caused by UV'ing. But also note the phone worked fine during my hour long drive home after the wakelocks and before the SOD

5 – Do you agree I have probably reached stability limit and should stick with 75 millivolts down instead of 100 (I have been back on 75 again for awhile...no problems)

Attached below is my battery voltage over the course of the day, annotated with the items discussed above.