Bought a used HP nc8230 and user informed me they could not get into bios. No problem I have diconnected the cmos battery plenty of times to reset bios. It does not work with this model because after a lot of research I found out it has the trusted platform module (TPM). Hp tells me the power on password is permenent in CMOS and the only way to get around this is to replace the motherboard. Just to inform you further about this, the minute you turn it on it ask for the power on password with a picture of a key. You don't even get a chance to try to Fkey into bios.