Hey, I had this question, I am currently running a pentium 4 631. Ive heard this processor can reach 4.0ghz easily, the problem is my motherboard will only give fsb options from 200-300 when using a 200 mhz processor and will often choke at 240 mhz. I've heard from people using my mobo that a BSEL mod is the solution for this. Will I be able to BSEL my pentium 4? and if I can, will it start up at 1066 (without changing the multiplyer).