My PC is no longer stable :[

[xioSlayer]

I built this PC a couple years back, and it has functioned great, but I am now experiencing severe stability issues :[

Here are the specs:
Win 7 64bit
XFX 650i nforce mobo (latest BIOS update installed)
core 2 duo e6750 (Arctic Cooling Freezer Pro 7)
2x2GB DDr2 G.skill (1066)
EVGA GTX470
SoundBlaster Audigy ZS2
antec 900

I recently upgraded from XP to Windows 7, and I also upgraded from 2 x 1GB Corsair ddr2 800 sticks so that I could push my OC further. On my xp setup, the Corsairs had me at 3.2ghz stable for a good while. Now I can't even achieve 3.2ghz on this same system, but so much has changed (OS, gfx card, memory) that I dont know where to even start.

My computer will just randomly crash, often times while watching an .avi video file (which uses very little of my CPU), whereas I can play Battlefield Bad Company 2 for great lengths of time, but I still get crashes.

The amount of time it can survive the Prime95 torture test is variable, sometimes 7 hours with no errors, other times it will crash within an hour.


My Event viewer is filled with warnings from WHEA-Logger stating:

"A corrected hardware error has occurred.

Reported by component: Processor Core
Error Source: Corrected Machine Check
Error Type: Cache Hierarchy Error
Processor ID: 0"

What does this error indicate?

These warnings are from the moment the OS loads up. Is it possible my couple years of mild OC caused my processor to mess up? or could these processor error indicators be caused by other components?


I also get (less often) these errors in the Event Viewer,

"Driver ACPI returned invalid ID for a child device (3)."

I'm not even sure what that is referring to.

Can anyone please help before I pull my hair out? :[ I've normally been able to solve most computer problems since I spend a great deal of time with computers, but now I am stumped, and broke, so I need to work with what I've got.


EDIT: Right now, i have my old RAM in, and will be seeing what kind of results occur. however, I'm still getting those Warnings and Errors in Event Viewer, Does anyone know what those mean? so i doubt its the ram at all.

 

[WR2]

What power supply are you using?

 

[WR2]

Also... what voltage do you have going to the RAM?

 

[Indy-Go]

You may have damaged your processor. I had similar errors when I had OC'd an AMD Proc. over a few years span and then tried to Dual boot / upg the system from win98SE to XP. I ended up getting a new CPU of the same like - which was much cheaper at that point then it had been when I first purchased it.

 

[xioSlayer]

I'm using an "Antec NEO ECO 620C 620W Continuous Power ATX12V v2.3 / EPS12V 80 PLUS Certified Active PFC Power Supply"

I've tried ram voltages from 1.9-2.1 (although the packaging suggests 2.0-2.1)

I have reason to believe that my northbridge may have been getting too hot. When OC'd it runs fairly warm, but I now have a fan blowing on it. and this is AFTER i cleaned the dust of the northbridge heatsink. So its possible that it was even hotter with the dust insulating it.

Does anyone know how I could rule out which part might be causing it? my intuition says its the northbridge, but I don't understand the micro scale mechanics of how physical degradation can cause instability versus just being fried altogether.