no keyboard

You should be able to enter STARTUP by pressing DEl during POST, reset the default BIOS and try restarting.

Two options I know of:

1) test with another mouse and keyboard

2) Sounds like a dead mother board

Check to see if the lights on the keyboard come on. Make sure you have the keyboard in the keyboard plug (not the mouse plug) this can cause some strange things. If you do see a light than it is ok...go into the BIOS and check to see if it is either disabled or if you see any other odd configurations. If you can try to get a BIOS update from a friend (Make sure you know what your doing if your going to flash the BIOS). Another fix would be to use USB keyboard and mouse. If by chance your PS2 plugs are bad I know the USB will work...you can also think of this as a small but nessissary upgrade, USB is very good when it comes to KB & MS. Email me if ya want. Ill get ya up and goin.

what kind of keyboard??? If usb, make sure it is in the first slot, accept the bios error and wait a few minutes after windows fully loads. If PS2, then look for the lights coming on, if they do not, then try reseating them, making sure they are in the correct places (keyboard/Mouse). If still nothing, try removing the mouse and see if the keyboard works. If not, and you cannot get into the bios, try another keyboard /mouse. If it isnt working by this point, your port on the motherboard is probably dead, consider
1. replacing the motherboard
2. getting an expansion board for PS2
3. If the system is old, then it might be a good idea to replace it.

I didn't read the other posts but are the mouse and keyboard connectors in the wrong holes?