Xserver idiosyncrasy in 4.x.x?

[Technoslick <technoslick adelphia net>]

I recently changed video cards in my RH 9.0 box, which shares a 17" 
Samsung 17GLi monitor via smart KVM switch. The previous card was an 
ATi Rage Pro 3D and the one in there now is a RIVA TNT2. The latter 
is much more card, so I am quite disappointed at the results that I 
am getting. Specifically, I now have a problem in screen display 
between the Win 98 and RH 9.0 workstations sharing this monitor. Now, 
when I switch from the Win 98 box to my RH one, the RH display is off 
screen to the right by about a half inch. Adjusting this brings it 
back to where it should be, but switching back to the Win 98 box 
causes that display to be proportionally off the other way.

The video stats for the Win 98 box are 1024x768, True Color, 75 Hz. I 
cannot do better than this. The stats for the RH box are 1024x768, 
Millions of Colors, 75 Hz. The same as the Windows box.

So, if both displays are driving the same graphics screens, why the 
difference? Why with this card and not the previous one? Anyone have 
this happen to them? Any solutions?  I've looked at XFConfig and made 
some adjustments. Nothing seems to matter. The newer 4.x.x XFConfig 
no longer lists screen possibilities, so I have no idea where to 
change them.

TIA

T