I've got a q6600 with vid 1.2125. The highest stable oc I have achieved is 3.4 at 1.35vcore +.2nb and +.2fsb with idle temps in the low 30's and high 40's-low 50's running prime95. I have had it up to 3.5 but it took 1.6vcore and idle temps were 58-60. From everything I have read this doesn't seem right. I know increases in speed require exponential increases in vcore and I know every chip is different but it seems like I should be able to push this chip a bit higher. My systems is:
ga p35 ds3l
4gb corsair dominator pc6400
I'm certainly not disappointed with 3.4ghz but I am curious, if there is a valid reason, why it won't go higher.
How about you establish if your board has a large VDrop and droop first?
Put the thing at stock, disable speedstep, and manually set the VCore to 1.2125 and re start.
When you hit windows, look in CPUz and watch for your Idle voltage. Make note of the highest it flickers, and then run prime 95 small ffts on all 4 cores, then list what CPUz says your VCore is while running prime for at least a minute. List the lowest value it flickers to.
Your chip by itself will need around 1.3250 volts while loaded to get 3.6.