What other voltage adjustments have you made? There are quite a few posts earlier showing some of our settings, have you checked those out?
I went through most of the posts here, but it is a 38 pages thread, it appears to be most of you have Q6600. i could have overlooked something. , could you kindly send me a direct link or somthing

Have you tested to establish the CPU FSB limit? You may be trying the impossible - its an E6750 and there is no guarantee that will be able to do 450x8. If its not an ES that would be deemed a very good overclock on that chip.
Do u mean lower the multiple and see whats teh max fsb that this cpu can take up to? i have done that, at 7x, it boots up to 500, on 8, 450 wouldnt even get me to windows loading.

Anyhow, i know there are lots of tweaking here and there you can do. But since my OC knowledge is sort of limited, i was hopeing some of u more experienced guys can give me some BIOS setting tips to get it going.