Dropped something on my cpu tower and now...

Help!!! One day i knocked my 2-3 lbs speaker on my cpu tower. It shut off my computer so i reached down to urn it on and it went to the compaq screen but with limes rumning down some areas so it wasnt the full picture for startup. Then it freezes (cntrl alt dlt and F8,1, and 10 dont work) the most i got it to do was press F1 real quick and it said entering setup... But then doesnt respond! Does anyone know how to fix it, how much it costs to fix, or if it is fixable.
Thanks!!!