Hi guys. I'm currently going through the settings on this board trying to get the best 24/7 prime stable OC i can, i have a QX9650 with 2x2gb of corsair XMS3 1600 9-9-9-24 1.8v (stock settings) memory.

I spent all day yesterday cranking the fsb up one mhz at a time, with 1T memory @ 7-7-7-14 (2.15v) and 9.5x multi, and i managed to get to 431mhz before windows started crashing on loading. This gave me a personal best of 11.5s~ on superpi 1m, and was actually game stable, but what a bummer when i tried a prime run and 1 or more cores dropped out after a minute

So today i've tried lowering the fsb back down (i can actually get a 24/7 stable OC of 4.4ghz from a 11x multi on 400fsb, but i wanted to see if i could drop the multi and increase the memory a bit [1:4 cpu333]) and to my dismay i couldn't get any kind of decent fsb overclock, even when i dropped to 420mhz. At that point i decided the memory settings may not be my problem, so i started looking at GTL values on the cpu as i read these can be tweaked to provide stability if certain cores are dropping out during prime. Now i have no idea what these actually do, i'm just going by other people's advice, and i've been told that if gtlref 1 is 5 steps lower than gtlref 0, stability increases. That tallies with the anandtech preview article (though they were testing a c2d) where they used -1 and -6. I figured i'd start there, so i set -1,-6,-1,-1. That got me stable for a little longer, so i was glad that i might be on the right track. Other cores have started dropping out after 10 or 20 minutes now, so i'm just doing a plus or minus step here or there on whatever core is needing it, and hopefully i'll land on a stable setting... Not too proficient i know but i'm pretty new at this. I figure once i do land on a stable GTL setting i can perhaps try to increase the fsb again and see what happens.

One thing is for sure so far, when i was rock stable @ 4.4ghz from 11x multi on 400fsb / 1600mhz memory ALL of my gtl values were at default/auto. So thus far i can conclude that increasing the FSB on a quad core will require GTL tweaking!

My other bios settings right now:

cpu - 1.41v target, 1.39v actual
cpu PLL - 1.5v~
vpu VTT - 1.5v~
NB - 1.67v
NB GTL - +2
SB - 1.5v

dram - 2.15v
dram pull up / pull down / ref all Auto, i'd appreciate someone explaining what these do and what i might do to increase OC'ability / stability.

memory timings currently all auto except 7-7-7-21 2T

Thanks!