My first post, and before you all point me to the guides I have done nothing else but read and try them all for weeks.
My problem is this:-
My Q6600 is stuck at a FSB of 300x9(which it performs rock solid) 301 to 319 stuck on post screen and only clear cmos will work. At 320x9,8,7 or 6 has booted into windows a couple of times but usually locks(no mouse) or restarts. I have booted into windows at 333x9 and I thought i has sussed it but when I checked in cpu-z I was at stock 266x9.
321x9,8,7 or 6 upwards it will post fine but get a overclock failed screen cpu/memory which gives me the option to default or last known good config, I prefer this screen cos I am sick of clearing cmos.
The reason I ask am I the worst overclocker is that my fist system used an E6600 and Asus p5n-32sli se deluxe which I couldn't get past 2.7ghz. The southbridge chip died on that mobo so i got the Gigabyte GA-N650SLI-DS4 and fitted the same E6600 Which was still stuck at 2.7ghz, so that says to me must be a bad chip and not 2 poor mobo's. So I buy a Q6600 and guess what the same poor overclock. Now the only constant between the 2 systems now is my Corsair xmx2 800mhz c4 Ram which I have had in both, could this be my problem?. I have tryed everything I have read and don't get any further, have even considered getting a pro overclocker on it but don't know wher to go in the West Yorkshire area ( any suggestions?).
What ever other info you need just ask and i will post straight back.
Thanks for your time,
Ceefna

did you apply enough power to every component?never see you mention in your post.

your ram isnt the issue. In bios set the ram to 1:1 ratio with the fsb.
Again you havnt mentioned your voltage settings.
Set all voltages to normal (you dont want to increase pci-e voltage). Maybe increase the NB and FSB volts one step. Again what are your current settings?

overclocking is a personal thing and trying to push things yourself.or you just want performance gain.then you need to pay someone to do it.or you sign a piece of paper says "IM THE ONLY PERSON RESPONSIBLE FOR THE OVERCLOCK AND ALL THE DAMAGE CAUSED"

Have tried changing vcore in stages upto 1.4v, also increased fsb and northbridge from 1.2v( think mobo's std) in stages to +.3v which is max. If i set my bios to 300fsb linked then 1:1 then mobo sets ram speed to 1200mhz, if i set it to linked/sync it sets it to 600mhz this is 1:1 right? at the moment all voltages are set to normal exept memory which is set to +.2 as my ram is rated 2.1v. Can't understand how it is rock solid at 300fsb on stock voltages and no post at 301+ whatever voltage i set. I have disabled all virtualisation stuff etc. Thanks for your help if you have any more suggestions.
Ceefna

just to let you know.650i chipset dont overclock well as P35 or even the P965.and the Nvidia chipset is specially poor with Quad core overclock.

New mobo then me thinks.
Thanks anyway

iluvgillgill is right. I had same problems w/ a ASUS P5N-E SLI 650i. I was totally unable to OC past 2.6Ghz. Tried everything and even asked for help on this forum. I found out that others w/quad core cpu's had no luck OC'ing with 650i & 6XXi (the next higher one) mobos. I switched to a p35 mobo and bam -- I'm OC'ed to 3.4Ghz 24/7 stable without even a sweat. I then paired the 650i mobo w/e6750 and it was able to oc....3.6Ghz 24/7 stable.

i heard the new 750i had improve the overclocking function.you can swap to that board and try it out.