T500 freeze on battery, can't open task manager

[zhk-t500]

just got this T500 a week ago, Vista Ultimate 32. it works fine plug in, but it often freeze after every 10-30 mins use on battery (often when I was on a bus or train, that is, when the laptop isn't stably placed on a secured surface). when it freeze, keys on keyboard are still functional, number lock and cap lock and even the little light bulb on top of the monitor can be turned on and off. mouse pointer is also working.

when the screen freeze, both Alt+Ctrl+Del and Ctrl+Shift+ESC don't work, there is no way I could end task, all I could do is to do a hard power down by press and hold the power button. and the freeze problem would occur again in 10-30 mins, and the program that i was running dont seem to matter, it freezed on Word, Mediaplayer, iTune... everything...

any idea where is the source of the problem? bad battery? Vista problem? hardware? or active protection?

[BillMorrow]

well, you can test for active protection problem by shifting the thinkpad while it is working..
watch the icon for AP and see if the problem reappears..
BUT, it sounds like something is loose..
battery is not it because it would just totally die..

possible a plug or a bad solder joint..

all this conjecture is based on your comment that it only happens when on a train or similarly on an unstable and moving surface running on battery..

if you can replicate the problem at home while moving it, try connecting an external display to see if only the display is frozen..

the more i think about this the more i thing its an esoteric hardware problem requiring a warranty call..

welcome to the forum..

[zhk-t500]

well, looks like this problem isn't something new, however there is no "real fix".

the temporary fix is to either disable APS or disable Hybrid Hard Disk Power Saving Mode. they just don't work together... it seems the function of running the system on turbo memory on battery conflict with APS.

I found some threads on lenovo forum, exact same problem... the problem was on T61/X61... and it is still there in my T500...

Tech support acted like they've never heard of anything like this when I called, and tried to solve the problem by sending me a new battery even though i told him that it is probably some problem with APS...

a new battery is a good thing anyway... I'll forgive them

link to the threads on lenovo forum:

http://forums.lenovo.com/lnv/board/mess ... e.id=16290

http://forums.lenovo.com/lnv/board/mess ... 381#M12979

http://forums.lenovo.com/lnv/board/mess ... ing&page=1