All signs pointing to dieing CPU?

[darkrider01]

Here's the story:

Machine starting rebooting randomly after I decided on a whim to return everything to stock clocks (2GHz, 1.35V). Prime95 shows failing on Core 0.

So...I overclocked it back up to 2.5GHz (1.43V) and Windows wise, it is much more stable. However, it still fails Prime95 on Core 0. Core 1 is happy as can be.

Is one of my cores on it's way out? What tests should I run to help make a conclusion?

As always, thanks for all your help!

[stevemedes]

hmmm. prime failing at stock clocks is not good... try updating your bios and running with different RAM sticks if you have em. Run memtest to make sure your RAM isnt the culprit. It also could be that Vantec PSU. I dont think thats too good of a PSU, especially if ur running 2 7800gtxs.

[darkrider01]

The PSU has always been fantastic (been running the dual 7800's a long time). I tested it with a digital voltmeter a while back, and it was within 0.1V on all pins....but all hardware dies eventually. I'll check that again, but if it was a power issue, I would think both cores would be acting similar.

Is it possible to run Memtest in windows or does it need to be run in a DOS environment? The only "extra" RAM I have around is a single stick of PC3200.....yuxors.

Sorry if I sound defensive....I've always been like that.

Thanks Steve

[stevemedes]

Originally Posted by darkrider01

The PSU has always been fantastic (been running the dual 7800's a long time). I tested it with a digital voltmeter a while back, and it was within 0.1V on all pins....but all hardware dies eventually. I'll check that again, but if it was a power issue, I would think both cores would be acting similar.

Is it possible to run Memtest in windows or does it need to be run in a DOS environment? The only "extra" RAM I have around is a single stick of PC3200.....yuxors.

Sorry if I sound defensive....I've always been like that.

Thanks Steve

I think they do make a memtest version for windows now, not sure. I always had a burned bootable CD with it on it. The proggy is called Memtest86.

Good luck and let us know how it goes.

[darkrider01]

Well, all is good now. Not sure exactly what fixed it. I pushed the "Defaults" button instead of manually setting my FSB clocks, and it passed 18 hours of prime95 with no issues at all. I then reclocked it back up to 250MHz FSB (1.43V) and Prime95 ran great. I'm at a complete loss. I thought that I might have been having an undervoltage issue on my 120V power coming into my machine, but I have an AVR UPS that would have fixed that.

Do computers have PMS?

[FastRedPonyCar]

Originally Posted by darkrider01

Do computers have PMS?

Yes.

I pulled a stick of ram out of my machine and put into my wife's motherboard to help it out a little and my motherboard all of a sudden decided that it would pick random latency times to assign to my ram. I couldn't for the life of me understand why my machine would randomly reboot and somtimes just reboot during the windows loading screen.

It never dawned on me to check the timing since it typically stays at defaults. It was the last thing to check on my list before throwing it out the window. good thing it was the problem!

[Slammin]

Originally Posted by stevemedes

I think they do make a memtest version for windows now, not sure. I always had a burned bootable CD with it on it. The proggy is called Memtest86.

Good luck and let us know how it goes.

Yes, there is a memtest.exe that runs under Windows and it is more definitive than any dos based test IMHO. I've had several cases where my bios-based memtest would be 100%, yet memtest.exe under Windows would detect errors.

Granted, the bios-base test detecting erros almost always indicates hardware failure if you are running stock, whereas the Windows based test can uncover overclocking issues. Using both is a must if you overclock.