Good morning people, I'm a 'newbe' here, and this is the 3rd time I've tried to post this question - hopefully it'll show up this time!! - lol

I'm hoping someone can help me please?.
I have a desktop computer here, with a Foxconn 661FX4MR-ES motherboard running Win2000. Some while ago the computer refused to start-up, after running for years without any trouble at all. I deduced that the power supply had crapped itself, so I replaced it (450 watt) with a new Thermaltake 600 watt ATX unit. Since then, the computer hasn't shown any display on the monitor, yet the computer seems to start up, (and shut down with the keyboard (and the computers own) power button). It makes all the right noises etc, just no display. The monitor (a Proview) displays 'Self Test, Monitor is Working' 'Check your PC or Signal Cable'. I have connected this monitor to another working computer, and it works fine, and I have also connected another working monitor to the Foxconn computer - still no display, so I'm dead sure it's a computer fault. I'm assuming that the power supply 'fried' the onboard video 'card'.Now, the question is: Can I plug in a separate graphics/video card into a spare PCI slot?, and what video/graphics card could/should I be using?

Thank you (in advance)
Peter