[XFX 780i SLI] Stablility lost, at stock

This is what I have:
XFX 780i SLI
Intel Core 2 Quad Q9450
2x2GB Crosair DDR2 800MHz RAM
2x2GB OCZ DDR2 800MHz RAM
XFX GeForce 8800GTX
Windows Vista Ultimate 64-bit
Everything is at stock.

Let me give you my story so far. Earlier this summer I started getting random BSODs, application and windows component crashes. After some troubleshooting it turned out one of my RAM sticks had died. So I took it to the store that I had bought it from to replace. They didn't have the exact same in storage at the moment but gave me some OCZ RAM instead. Now Memtest is happy again.

I was still having some issues though, and I figured the windows installation had gotten corrupt, so I reinstalled, but it didn't help. After some more troubleshooting it turned out my old Seagate 7200.9 drive had failed. It even started to make clicking sounds. I replaced it with a Samsung Spinpoint F1.

After another reinstall of windows I was happy thinking everything seemed fine. But I started getting some crashes again. I figured it was caused by the heatwave we were having. (Have no AC)

When the heatwave passed and things were still crashing it turned out my installation was corrupt, again. So, yesterday, I reinstalled windows, again.

I am already having problems. Weird crashes and freezes. The machine fails all stress tests within seconds. Except Memtest, which shows no errors. OCCT and Prime throw up error immediately. SuperPI as well.

It feels like I am banging my head against a wall here. Please Help.

How long did you run memtest? Just run test #5 for like 30min.

Try defaulting all of the settings in bios.

Did you update bios before problems started?

meionm said:

How long did you run memtest? Just run test #5 for like 30min.

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I left memtest running over night. I did ten passes or so.

meionm said:

Try defaulting all of the settings in bios.

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First thing I tried.

meionm said:

Did you update bios before problems started?

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No, but I did update it later on as part of my troubleshooting.

Another interesting development. If I drop the CPU multiplier down to 6x (a 666MHz underclock) Prime doesn't error out. In fact, underclocked the computer ran Prime all night, last night, without errors.

Does this mean the problem is with my CPU?

Do you have another system available to test that Q9450 in? If you do, temporarily install the Q9450 into it and see if the problems follow along with the processor. But I would suspect the motherboard as the problem instead of the processor. My (rather limited) experience with Nvidia chipset Intel boards makes me suspect the board as the problem rather than the proc. I'm sure that Intel has sent out bad processors but I've never seen a bad proc from them.

EDIT: One other thought. What brand and size psu do you have running your system?

muddocktor said:

Do you have another system available to test that Q9450 in? If you do, temporarily install the Q9450 into it and see if the problems follow along with the processor.

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All my other systems are AMD.

muddocktor said:

EDIT: One other thought. What brand and size psu do you have running your system?

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An Enermax 600W.

Try turning off speedstep, c1e.

Set cpu voltage manually. Check what is the cpu voltage at 6x and higher multiplier compared to what it set in bios.

You, sir, are a genius. You just may have found the problem.

I have NVIDIA System Tools installed to tweak fan speeds. Turns out the it for some weird reason defaulted to changing the vCore to 1.520, which I believe is way overkill for a 45nm CPU. After uninstalling it the vCore came back down to 1.272. Now I'll leave it Priming over night and see if it is stable.

XFX 780i SLI are you using sli if so try 1 card.
Do you have the latest bios.
Many posts at Evga were boards suk with 4 sticks of mem.
Suggest you try 2 sticks of mem only.
Could have traded my 680i + 100 bills to evga for 780.
Everything is at stock.
I would take mem off auto.









=

Most of everything seems stable. The only thing still crashing is nvidias graphics drivers, but that's pretty normal.

So the vcore fixed it?