It's not in a tower PC, it is in a laptop. I've already tried removing the CMOS battery after I removed the laptop battery & unplugged it. I also tried holding down the power button for 1 minute, 2 mins., about 5 mins. and just leaving it out overnight. Looked everywhere for a jumper, but haven't found 1 on laptop MBs before. Thanx for the info, just can't use it on this system. Once again, it's a Gateway FX P-6860 (Model #: P-6860FX) that's running Microsoft Vista Home Premium (until I can install XP Pro).