AGP card

I have just fitted an AGP card to my XP pro system. Now the monitor hangs when being used for graphical related uses…ie games.
It is running 133/133ghz on a athlon 2000+ processor with a sis chipset. I have tried to download the updatefor the chipset to no avail..SIS just say their server is busy try again. for two days at all times I get this message. Im looking for driver called sis 5591.
Anyone help me……..Please.