Hi, I just got Vista 64 bit edition SP1 performance edition, I recently had ultimate edition but its been running too slow for me so thought I give this a try. When I try install, this comes up. FILE:\windows\system32\boot\winload.exe status: 0xc000035a info: Attempting to load a 64 bit application, however this CPU is not compatible with 64-bit mode. I got a good pc, how is it not enabled or is there a way i can make it enabled? System specs, Intel core 2 quad cpu Q6600 @ 2.4ghz 4gb ram 800mz nvidia 8800 gt 512mb vid card Vista gives my PC a rating of 5.6 also! If I can't have 64 bit edition and if this Vista too slow, i be reverting back to XP SP3 performance edition, however I have 4gb ram so prefer 64 bit edition to utilise it all. Any suggestions?

Are you trying to upgrade from the 32bit version? If that's the case you can't. You need to do a clean install, don't forget to backup all your data.

clean install