Possible mobo problem?

[Charitable help]

I thank all for the welcome but now I really need help. I am trying to help a poor person who does not have money for a real tech. The computer is a Dell running XP Home Edition and I have tried everything I know to try to boot it up. I took everything out of the motherboard and replaced each one at a time. I found out that there must be something wrong with the keyboard. When I plugged it in, the Print Screen , Scroll Lock and Pause lights kept blinking. When I unplugged it, I was able to get E Machine screen and then the screen with information which gave me the error message "no keyboard" Without the keyboard I could do nothing and now that is where the computer is stuck. I can turn it off and on but can do nothing else. I tried another keyboard but I get the same thing. This makes me think it is the motherboard connection. What can I do short of a new motherboard? Would a keyboard that has a USB connetion work? I began thinking the problem was the hard drive before the blinking lights on the keyboard began this morning. When I tried new memory to see it that could be the problem but nothing helped to boot it up. Now I am thinking it is just the keyboard. The CD Drive would not open before but now it will if the keyboard is not connected.Any suggestions?

 

[iss]

you can either try a usb keyboard or get a PS\2 to USB adapter and use it. they are only about 5.00