I have the abit kt7a-raid board and a locked 1.1G @ 11x100 thunderbird running 160M pc100. A guy I work with has a 850 thunderbird with high desity 512M 133 and his flies!. Can I run 512 pc133 @ pc100 speed? I know u can underclock a CPU but not sure about the memory. I tried to O/c my 900 and friedn it 2 days afer I bought it , so Im sticking with what I have.