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I use my desktop PC mostly for watching TV, downloading stuff and sometimes playing big games. Recently, I've been having some weird problems which I am unable to attribute to a particular component. Sometimes, irrespective of what I am doing, the monitor just switches off/goes blank and the system becomes dead!

I can see the power light glowing in the chassis, but none of the components seem to work, even the restart button. I thought the problem might be a loose contact between some components inside the chassis, so I opened the box, removed dust, re-fitted the TV tuner and graphics card. Still the problem persists.

I have yet to try switching off the UPS and then starting everything again. Is this a problem with my video card? How can I diagnose/fix this problem?


  • nVidia 8600GT graphics card
  • Core2Duo processor
  • Intel motherboard
  • Pinnacle TV tuner
  • 3GB of RAM
  • Windows XP
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Have you looked in the event log to see if there is anything there? – MDMarra Oct 15 '09 at 11:08
You mean, After the restart? I checked during one restart, but not for all restarts i have done so far. No errors! – vpram86 Oct 15 '09 at 11:10
up vote 3 down vote accepted

First you should check if there is a software condition that triggers the freeze. You can check if it only occurs running some kind of applications. For example, tv applications crashes may indicate a faulty tv tuner or video card, and crashes playing games that make intensive use of graphics may indicate a faulty video card.

There are many possible hardware causes: power supply unit, video card, tv tuner, system RAM, temperature issues (overheating), etc.

To check for hardware problems, you can start by disconnecting components one at a time and test your system. When you reconnect those components, they should be working again automatically.

To check for a faulty video card, you can try connecting the onboard video integrated on you motherboard (if it's available) or connecting a replacement card.

System RAM can be checked running Memtest from a live CD (you can use SystemRescueCd)

To check the PSU you can replace it or look for incorrect voltages and temperatures through BIOS setup.

Some causes of overheating are failing fans and dust blocking air flow.

share|improve this answer
THanks for giving multiple options to check! I am trying one by one. I dont see any crashes with respect to software because its just going dead irrespective of what i do... Even if the computer is downloading something overnight and doing nothing else, it will be dead when i wake up and see it in the morning.. I am going to look into hardware sides now... – vpram86 Oct 16 '09 at 5:53
Seems to be problem with PSU... :) replacing it is working like a charm! Thanks a lot for pointing in right direction! – vpram86 Oct 16 '09 at 18:00
You are welcome. I'm glad it helped. Generic PSUs are specially very likely to fail (and endanger all other components). – alfplayer Oct 16 '09 at 18:29

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