Ive got a Dell Vostro 3500 on Windows 7. A while ago I dismantled it to clean the fan out as it gets clogged and overheats periodically...on rebuilding I had an issue starting up at all using the power button, seems it went faulty/got broken in the process of taking it apart. Ive replaced the media control/power button panel with a new one and all seems ok except...
When I power on from cold, my laptop works fine for a minute or so - boots windows etc, but will instantly power off after a period of time. It will do this 3 or 4 times in succession and then work absolutely fine for the rest of the day. No error message or blue screens, just power off. Its as if it needs to run and warm up before it settles down, which obviously makes little sense.
It isnt always at a certain point (ie on windows start up when a particular hardware device is activated) - for example if it crashes and windows does a scan when it restarts due to incorrect closure it can still power off at this point before windows has started,so it seems like a time/heat related issue rather than, say, a driver or hardware specific issue when its activated on startup (although im no expert).
I have the newer motherboard with switchable graphics and as far as I can see drivers are ok and no conflicts etc.
Can anyone advise a possible cause? Its odd but I cant work it out.
The only known issue is that the new media control strip I put in doesnt quite work...the power button works and it lights up the bunch of power/wireless/caps lock lights and these function correctly, but the media buttons (play, stop, volume) do not work at all, and constantly are dimly flashing quickly. It hasnt bothered me too much as its primary a business laptop but dont know if this could be a potential bug that is affecting things.