QX9650 L739A644 + Blitz Extreme

[xgman]

George,
Congrats on the QX. You may find this kind of crazy, but I think you are having stability issues because of your FSB. My findings have always led me to stability issues whenever FSB was near 445, 450.... I cannot even boot Windows after 450 FSB, 455+ it will freeze at post. So, FSB has been a huge limiting factor for air/water on these QX's. Just a little FYI from my personal experience.

Try 10 X 400 with 1.3625 (bios selected) vcore and if you have ample air cooling capacity I am pretty sure you should be quad prime stable set to (12meg cache setting in multiprime).

I know, because you are raising the multi, bus speed and ram will be slower. But I see you are running CAS7 6-6 on those sticks. To combat this I have found the best setting on a 4.0 Ghz overclock for me was:

10 X 400 , 1.3625 Vcore bios selected (1.31 after vdroop)
Ram at 1600 mhz, Timings: 6-5-5-18 (2.05v , 1T)

As you can see, even though you are lowering FSB, you still have the ability to run CAS6 and tighter timings + I am pretty sure you will be able to achieve 4.0 GHz low volts stability.

Let me know of any results.

I heard that if you can set Static Read Value to "9", it helps to get higher fsb. I think with the Storm G5 he can set volts to 1.5-1.55 without harm. I have my phase running at 1.567v (reported). I find the 9650 needs higher volts to get in the high 4xxx's and also higher fsb stable.

George, I had a bit of a hard time getting this cpu up there at first, and it does seem to need more vcore than those ES samples, but under phase it now seems mostly stable at 4800 mhz approaching 1.6v set in bios, Odd thing is with sub zero temps, coretemp 95.4 reads the first two cores 8 deg higher than the 2nd 2. Is this normal. I know the readings for sub zero are not accurate obviously, but why so much difference between sets of cores. All that said, I think that this is one of those times when the ES's were really hand picked for the most part.