My son is using a tv as his main pc scrren, recently it has stopped working with the pc cable. When we turn the computer on it send a siganl to the tv but as soon as it's loaded and hits the password screen the tv goes dark and says no siganl from pc, we are using vista and he has been playing SW:Tor on it which i believe can cause an issue
As the computer is booting press and hold your 'F8 Key' which should bring up the Windows Advanced Options Menu. Select 'Safe mode with networking' and load into Windows. If you're able to load past the log in screen re-install your video card drivers.