pentium 4 pc computer complete set up (faulty) *

PLEASE NOTE THIS IS FAULTY HENCE PRICE 25 It was working fine but now seems to boot up but no picture? could be an easy fix for somebody? Pc computer running fully activated windows xp professional with service pack 3.... intel pentium 4 3.20GHz 40gb sata hard drive 1gb ram memory 128mb ATI Radeon 9200se AGP Graphics Card integrated sound card floppy drive dvd drive with keyboard & optical mouse & 17" ctr monitor ~(not lcd)