Prime95 error -- please help

[imported_Meridian]

I'm currently running an Intel Core 2 Extreme QX6850 at the factory clock speed of 3.0Ghz. However, whenever I run Prime95 (version 25.5), I consistently get an error within the first 10 minutes (if not within the first minute). I'm running Core Temp 0.96 and the temps look fine.

I tried overclocking the chip a few weeks ago, but decided against it, and went back to the factory settings (i.e., 9x333FSB @ 1.325v). But now, as I mentioned, I consistently get an error executing Prime95, even if I bump the voltage up to 1.4+.

Any help?

Thanks,

Ben

 

[Thor86]

Try running Memtest and test your ram/settings for errors first.

 

[Mondoman]

(or, more precisely, memtest86+)

 

[myocardia]

When all else fails, read the directions.

 

[imported_Meridian]

Originally posted by: Thor86
Try running Memtest and test your ram/settings for errors first.

I ran Memtest86+ (v1.70) this morning without any errors. I completed 6 passes of test #5, and 1 pass of the default test.

Prior to running Memtest, I went into the BIOS and loaded the default settings.

My Core Temp (v0.96) readings when I ran Prime95 (v25.5) this morning did not exceed 45 degrees Celsius. The torture test with Blend detected an error within two minutes. The torture test with Small FFTs detected an error within 7 minutes.

The only other thing I can think to mention is that this system is less than a month old, and came factory installed with Vista. I recently formatted the drive and did a clean install of XP.

Thanks again for the help,

Ben

 

[Thor86]

Nvidia 680i boards are finicky, and most default settings in the bios need to be tweaked even at default runs. Better do a search on your board's bios settings and go from there.

Maybe even tweak the vcore, nbcore and vdimm by .1 voltages and see if that helps with Prime95 testing.

Start with nbcore/vdimm by upping them a bit, and do a blend test and see if it passes for an hour initially.

 

[badnewcastle]

Vista and 680i or for all I know any ram.... make sure your ram is set to the manufacturer's specified timings and voltage... I had a few problems with install and with long loading times... reverting back to the mfr's specified timings and voltage (instead of putting it on auto in the bios) fixed this and some other errors I was getting.

 

[imported_Meridian]

Originally posted by: Thor86
Nvidia 680i boards are finicky, and most default settings in the bios need to be tweaked even at default runs. Better do a search on your board's bios settings and go from there.

Maybe even tweak the vcore, nbcore and vdimm by .1 voltages and see if that helps with Prime95 testing.

Start with nbcore/vdimm by upping them a bit, and do a blend test and see if it passes for an hour initially.

OK, a total noob question -- what is nbcore/vdimm? I upped the memory voltage, but not sure what nbcore/vdimm is or where to find it in the BIOS.

Thanks again,

Ben

 

[Thor86]

vdimm is memory voltage, and nb (memory controller [north bridge]) voltage, not sure what 680i bios calls it though, sorry.

 

[imported_Meridian]

OK, i upped the memory voltages, but Prime95 is still detecting an error at about 7 minutes into the blend test. Otherwise, the system seems rather stable, e.g., it always boots fine, it runs 3dMark06 fine, etc.

Is it possible that the CPU is damaged? Or would I get more noticeable signs if it were?

Thanks again,

Ben

 

[The-Noid]

What is the error?

Rounding errors are usually memory related.

CPU errors usually the program fails or your computer reboots.

My guess is your memory doesn't have enough voltage. What is the exact model of memory so I can tell you what voltage to run.

 

[imported_Meridian]

It's a rounding error. The memory is PDP DDR2-6400 (800Mhz). I don't have a specific model number, but if it would help, I could probably open the case and check the sticker on memory sticks.

Thanks for the help,

Ben

 

[badnewcastle]

Originally posted by: Thor86
vdimm is memory voltage, and nb (memory controller [north bridge]) voltage, not sure what 680i bios calls it though, sorry.

Not sure what it's called on the XFX but my MSI calls it NB Voltage...

I also read on MSI forums to put FSB VTT at +2-4%, I have mine at 4%; this may help you aswell.

Edit: Check the forums at XFX see what they are saying about OC'ing...

 

[imported_Meridian]

Originally posted by: Yoxxy
What is the error?

Rounding errors are usually memory related.

CPU errors usually the program fails or your computer reboots.

My guess is your memory doesn't have enough voltage. What is the exact model of memory so I can tell you what voltage to run.

According to CPU-Z, my memory is PEP21G6400LL. I looked up the specs, and the voltage is supposed to be 2.2v. I had that right, but my timings were totally off. I changed the timings to 4-4-4-12, and Prime95 ran for 10 minutes before an error. Not great since I haven't overclocked at all, but it seems like a step in the right direction.

Do they above settings seem right? Anything else I should try? The next step is to look at setting specific for my XFX motherboard I suppose...

Thanks,

Ben

EDIT: but the Small FFT test still detected a rounding error in the first minute...