MSI 790fx-gd70 & 955BE not stable with stock settings.

harrell98

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Mar 6, 2010
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Ok, well it has been a while since I last upgraded my PC so I built the following:

MSI 790fx-gd70
AMD Phenom II 955BE
OCZ AMD Black Edition 4GB (2 x 2GB) - OCZ3BE1600C8LV4GK

At first I thought everything was running great, but I was getting some random hard locks within Windows 7. Being the first time I ran Windows 7, I just cursed Microsoft.

I then remembered, that I had forgot to set the memory to 1600mhz with the correct timings (8-8-8-24). Once I set this, I started having all kinds of hard locks. I thought it might be a memory issue, so I ran memtest86+ for about 24 hours with no errors at all.

Now, I began to think it could possibly be the CPU. I tried running a Prime95 blend test, but the system would hard lock as soon as the test began. I had the same results with the Large FFT stress test as the blend. However I am able to get the Small FFT to run fine. Could this possibly mean a faulty northbridge on the motherboard?

If I set the memory to 1066mhz I can actually run the Large FFT...I don't know for how long though. This is driving me nuts! What do you guys think? Memory, CPU, or motherboard?
 

arges86

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i honestly never use the large FFT stress test.
I only use the Small FFT and Blend.

make sure your CPU is not overheating. Heat will cause your cpu to fail. if your CPU isn't getting to hot (i think around 70 degrees C... but i don't know the exact temp. for your CPU) then it will 'leak' and give errors.

you can always RMA the CPU and get a new one. Every-now-and-then a bad one slips onto the market
 

JofaMang

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Jun 14, 2009
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You could try a couple things.

-Loosen (raise) the timings on your memory manually. AFAIK, memtest tests only the memory integrity, and not the cohesiveness with the CPU. Tight timings may pass memtest but still fail when run in normal operation.

-You don't mention voltages with the memory. Are you adjusting the voltages when running it higher frequencies, as per manufacturer specs? The fact that you lower the memory to 1066 and achieve greater stability is a hint towards memory issues, or as you suggested, mobo issues.

It is hard to say for sure, but it is entirely possible that your mobo or your CPU is in need of RMA. If you purchased them all from the same place, take them all back to the same place and explain your problems. If it is recent enough you may be able to swap. If you ordered online, start the RMA process on the mobo first, imo. My gut feeling from what you describe is mobo related, provided playing around with the memory as mentioned above doesn't help at all.
 

harrell98

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Mar 6, 2010
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I did set the memory to 1.65v, which is the stock voltage for the memory. I haven't tried increasing it or decreasing it, because I don't really know much about messing with voltages. The last time I built a PC, there were no needs to adjust any of these things :na:

I did let Prime95 run a Small FFT test for over 12 hours with the memory at 1600 Mhz and it never had any errors. That would make me think that the CPU is ok, so it could very well be the northbridge chip on the motherboard. A Large FFT test that utilizes both the CPU and memory together hard locks the machine immediately.

I did just order all this from newegg last wee, so there should be no problem at all exchanging it. I was just hoping to RMA the right piece, so I won't be without a computer for an extended amount of time.