Random crashes at night

[Dlaw]

I leave my computer running at night so antivirus can run without getting in my way. The last two nights in a row, it has crashed and returned to my boot screen (I have GRUB handling boot). I ran memtest86 to 100% with no issues, ran CCleaner's registry scan, and only a couple of problems related to a recent uninstall of programs I don't use (ATI Catalyst drivers related to my on board graphics, did not have CCleaner fix), ran P95 for a couple hours with no problems, played a game or 2 of CoD4 (game crashed, but it does that randomly for some reason related to punkbuster, and I gave up trying to fix it a while back), and checked my process list for anything I didn't recognize. I did this all yesterday, before going to bed. By the way, it ran all day yesterday without a problem.

It crashed again last night. Yesterday morning, when I booted into Windows (after running memtest), I got an error stating that Windows has recovered from an unexpected shutdown. No such error today. Any ideas?

 

[Dlaw]

I forgot to add: I had the same problem a month or so ago, and upon closer inspection (and with my girlfriends step dad's help), I found that the DIMM closest to the CPU wasn't seated all the way. It has run fine since, until the past 2 nights.

 

[realmadrid12]

Get a mem dump and use minidump to open it a see what went wrong. Or post up the mem dump here. Once you get the code (eg. 0x0000007B) you can google it.

This is just a complete guess as there is no info to go on but if you are doing a virus scan you are putting stress on the HDD. If you have a secondary HDD controller on board try switching it to that controller and see if it happens again.
Generally the ports are a different color for the different controller.

 

[Archer0915]

Try dropping it back to a quad and setting the speed and voltage back to auto. I had the same issue with my 555 = B55. At first I thought it was updates but it seems that when the thing was idle too long the it would just crash and reboot. I added voltage and it fixed it but I finally decided to put it back to dual and OC higher.

 

[Dlaw]

That sounds like what's going on here. Probably a bad core then, right? I wish I could figure out which one it is, so I could just disable that one. Oh well. Thanks, I'll try that then.

 

[Archer0915]

That sounds like what's going on here. Probably a bad core then, right? I wish I could figure out which one it is, so I could just disable that one. Oh well. Thanks, I'll try that then.

Try upping the voltage a hair if that is the issue but I found that because one of the cores was not up to par everything was faster as a dual. If I want to use it a a quad for a crunch or fold I can and it is error free and no issues as long as I keep it under load.