Win7 Ultimate x64 - PC suddenly turns off/Recovery on restart

[DanUnderwood]

Hi folks,

I posted on here before after I was having trouble with problems when my computer suddenly turn off. Through a Mem86+ test, I found that one of my 4gb RAM sticks was faulty. I have removed this and sent it back under warranty.

However, it has not really cured my problems. The computer will still suddenly just shut off as if it was turned off at the wall. Then it will restart and ask whether I want to 'Start Windows Normally' etc. Sometimes I will get a brief glimpse of a BSOD, but usually I will just suddenly see a black screen.

Also, on occasion, the computer will hesitate when starting - I'll hear the fans spool up and down as it seems to struggle to draw power (dodgy power unit??). This can happen on a fresh start or after it's crashed. As well as this, after starting up from fresh following a clean shut-down (usually the next day), the computer is starting to run recovery programs or disk checks on start-up. This sometimes happens following the crash but, as I say, following a reboot after a normal shutdown. I usually let it do this, but these are new and becoming more frequent.

And finally, I usually run three screens to play EvE On-line. These will sometimes individually crash, which is another new thing.

When I was running WinXP, I had none of these problems. So it's all happened since installing Win7. Please help!

Stats:
-Win7 x64
-Installed over original Windows XP OS
-Full retail version
-Computer was brand new in March this year
-Win7 has been installed for about a couple of weeks

-i7 Quad Core @ 2.93GHz
-4gb of RAM (normally 8gb, but second stick has been sent of under warranty)

 

[DanUnderwood]

I have made accidental progress on my issue. I just put my headphones down and knocked a small ornament onto the computer. It did it's shutting-down thing. When it started reboot I gave the top of the computer a thump. Took the panel off and then gave the power unit a (gentle!) thump when it started up again. Same thing! So, a dodgy power unit! I fiddle with cables but it didn't repeat the problem, so I'm guessing the problem is internal. This is covered under warranty, but is it worth pulling the unit apart myself to see if it's a simple problem?