Video Ghosting issues with XP/Redhat 9 KVM - help?

[NaturalChiller]

I have two machines. An XP box and a Dell PowerEdge 600SC running Redhat 9.0. I bought a dlink KVM switch and set it all up. I am able to switch between machines using one monitor, keyboard, and mouse. The only problem is the video on the linux box is very fuzzy and there is a lot of ghosting of graphics. The graphics card on the PowerEdge is an integrated ATI Mach64, i believe. Should I upgrade to a better vid card on the linux box? Any help would be appreciated.