Won't take keyboard input

This machine is the 2 Ghz DP version, 2005.

It will chime and boot to the internal HD.

I lost the password so can't login.

I then try with the DVD install to reset the password.

It will not take any keyboard input combination to reset NVRAM, boot off DVD---nothing.

The keyboard works because when I tried some password input it prints on screen.

I took the HD out, put it back in and on an SATA channel it did not like. It did not boot.

I changed it and it booted but this time without anything on screen...it does not seem to boot completely.

I cleaned the tip of the video card. No luck.

Any help will be appreciated.

Thanks

I must also mention that I've removed RAM, battery, etc, to see if it's locked with firmware that's preventing the keyboard input at boot, but no luck. I think that's the real problem here....not responding to keyboard input during boot.