|My response above was directed at jimmy, who was wondering how a password request suddenly started appearing.|
I was under the impression from your first post that you knew the password and had cleared it but for some unknown reason you were still being prompted. But your post above indicates you don't know the exact password.
Anyway, many Gateway models of your type have a password-enable jumper on the motherboard. I didn't think about that originally since you didn't mention if he'd opened the case. But if that jumper is in the 'password enable' position then I imagine you'll still be asked for a password even if it's been cleared in cmos. You need to open the case and see if you can determine if you have the password enable jumper and if so, set it to 'disabled'.
Other gateway motherboards have the typical 'clear cmos/clear password' jumper. If that's the case you need to set it in the clear position, turn on the computer for a few seconds, turn it off and put the jumper back in the normal position. Then on the next boot you'll get an error about the settings and you'll need to enter cmos to set the date, time and maybe some other settings.