I changed a pc133 64 mg chip with a pc133 256 mg on a Biostar M6VCF, and now the system won't boot: the power light turns on, the cd player opens and closes, the hd spins,and the cpu & fan work, but I get no video. The keyboard lights up and turns off when I power up, but other than that, it stays off. The Biostar M6VCF manual says the MB takes up to three 256 mb dimms. I put the 64 mb dimm back, and still nothing. Any ideas?