GEforce 5200

Custom Built machine, AMD processor, 1 GB ram, 40GB HD
Geforce 5200 Video card
Running XP pro

It's been working ok for a couple of years.
Then after a recent MS Update the computer would only start-up in Safe Mode. I went back to an earlier "Restore point" but no luck.
Basically, if I try to start up normally it gets has far loading windows, but before the login screen appears the screen goes blank and the monitor goes into powersave mode (so I guess its no longer seeing and video signal).

To cut a long story short, I decided to re-install everything from scratch.
Everything was OK until I installed Service pack 2 and the problem re-appeared. Luckly this time going back to an earlier restore point cured the problem. well sort of...
When I reboot the system complains that it has found new hw and takes me to the normal wizard but if I install the drivers (latest of this site) the problem re-appears. If I ignore the "found new HW" and wizard everything seems OK.

Any Ideas what causes this and how is the card working with no drivers.
I checked under "Device Manager" and it doesn't show the card but does show under other devices, "VGA" with a yellow warning icon

 

Do you install mobo's Chipset,VGA,LAN,Audio drivers after reinstalling Xp?