E6550 Failing Prime95 at Stock Speeds?

For the heck of it I wanted to test my computer at stock speeds. Prime95 was the first program I was going to try, expecting to do others. When I open up p95 and do the torture test, either the default blend, or the larger/smaller varieties, one of my working threads fails within a minute... Why?

When I change the torture test to do the 8k iterations or whatever, I can keep the test running. I had coretemp in the background and temps never got above 42*C. I have a GA-p35-DSR3, a 520HX psu, and a 8800GTS 640mb. For cooling I have the TR Ultra 120 Extreme with 2 of those S-Flex fans on it.

When I put my computer together, I did not change ANY settings regarding FSB, voltage, etc. Only the boot sequence was changed. Did I miss something?

Let me know what kind of screenshots/information can help you help me figure this out so I can start moving forward. Thanks!

When it pass at 8k the CPU is ok. Blend starts with large FFTs, a fail there is memory error. Up memory voltage or reduce speed/loosen timings.

yeah but shouldn't it work stock? the memory should be set that way it shouldn't need upped volts. wtf?

Well I checked CPU-Z and my memory is rated at pc2-6400 in the screenshots, but the actual sticks are the pc2-8500 ballistix tracers... Apparently I need to fix something there...

The BIOS will automatically set your RAM voltage to 1.8v. Your RAM needs 2.2v, and you need to set it manually in the BIOS. Actually 2.0-2.15v may work fine, but 1.8v is a no-go.

Ok I went into the BIOS and the M.I.T. Tweaker part and changed the overvoltage t 0.4V. So far the test is running as expected, but I'll see what happens and report back.

::erased other stupid question::

Ok so the test ran for 6 minutes and the 1st worked thread crapped out. I think I set the voltage for the ram correctly, but some have said that the Gigabyte boards have vdroop? Does that mean that the 2.2v is actually lower then that on the board?

Or am I trying to accomplish nothing for no particular reason?

You also need to change the memory multiplier to 2.0.

Vdroop has to do w/ the CPU, not the RAM, but there may be some voltage drop to the RAM as well. I wouldn't worry about it, though.

Ok got it to work. Thanks! Now I just have to find time to OC this thing.

Instead of running Orthos/Prime to find memory issues. Get the bootable CDROM version of Memtest86. Stick that in and see if it throws errors.

You can get it here -> http://www.memtest86.com/download.html

I would recommend memtest as well, but I had issues w/ it on my current rig. I couldn't pass memtest even at 2.2v 800MHz w/ timings set manually or set automatically w/ my Ballistix 800. Neither stick would pass on its own either. Even setting the timings to 5-5-5-15 still threw up errors.

I can run P95 small, large, or blend all night at 900MHz 4-4-4-6 at 2.15v, though. 1080MHz 5-5-5-9 seems to be stable as well.

BTW, I was using memtest 1.70+ via floppy.