wow too.. I rememebr this thread when it was posted. =) glad to c u found the problem.. who would have thoguht it was the monitors refresh rate.. something to keep in mind in the future.. =)
Ok, after reading all of this, the only thing I haven't seen mentioned is a surge protector. Are you running one? Is it faulty? Are you running an uninterruptable power supply? Try changing to a better surge protector, not a $5.00 Kmart one.