I had bad luck with my first e6300. It wouldn't post above 400mhz. under 401 was fine, but 401 and above won't work. With the chip I use now, I can boot at 532mhz, and clockgen to 534mhz. It isn't stable, but that is because of the vdroop on my S3. I can't get this to be stable over 507mhz, but I think vdroop (even after the mod) still plays a role as well as nb voltage. I sure would like to use my chip at 528mhz fsb like I could with it in my S3.