GA-X58A-UD3R3: prime95 failures

[howardt]

I can't seem to get a set of BIOS settings for my GA-X58A-UDR3 that lets it pass the prime95 blended test (though it will pass the prime95 small fft test).  I'm suspecting memory setting problems, even though memtest86+ runs without detecting errors (maybe it takes a combination of the cpu's getting hotter by doing the prime testing to get the errors to happen?).  Also, windows 7 runs fine for a while (hour or so), but then freezes.  I'm running out of ideas, and would appreciate any from here.

System:
Gigabyte GA-X58-UD3R (rev. 2), BIOS version fc3 (same problem with fb)
i7 970 3.2GHz
memory: 3Gb x 6 of Muskin Enhanced Silverline 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Desktop Memory Model 998768

Most of the Bios settings are on Auto, but I manually set the memory timings to 9-9-9-24. The BClk is 133Mhz and the CPU freq multiplier is 24. So CPU frequency is 3.2Ghz, QPI freq is 4.85 Ghz, Uncore freq is 2.7GHz, memory freq is 809Mhz.
Current voltages:
CPU Vcore: 1.21875V
QPI/Vtt: 1.200V
QPI PLL 1.1V
IOH Core 1.1V
ICH I/O 1.5V
ICH Core 1.1V
DRAM Voltage: 1.5V
DRAM Termination: 0.750V
Ch-A Data Vref: 0.750V

The cpu temps are around 45C when running primes.

On advice from Mushkin, I tried upping the CPI/Vtt to 1.3V and the DRAM Voltage to 1.54V.  Didn't help.

[Dark Mantis]

As you rightly summised normally if Prime fails on the blend tests it is a memory problem. When you ran Memtest86+ did you do it on one module at a time and for at least 10 loops each?

[notshy]

Can you please post the recommended settings from Muskin - have you checked on their forum or on their data sheets.

Try QPI to x36 ? Have you enabled all SpeedStep and C1E and all other C-States in CPU features?

Have you tried upping your DRAM voltage and also QPI/VTT ? Depending on what Muskin say - but I've seen a lot of DDR3 RAM that needs 1.65v and QPI/VTT at around 1.3 or 1.355 to get it stable.