I'm not sure I can agree that CPU speed will have no effect on Voodoo 1 performance. If this graph is anything to go by, there is probably a noticeable difference in some games : http://www.tomshardware.com/reviews/big-cpu-shoot,84-2.html. Granted that was using a Voodoo 2. I think its probably easier to find a 300A than a 300.
If there are games that mix the 3D accelerated graphics from the Voodoo and 2D graphics from the 2D card, then the KVM or dual monitor setup just won't work. While Matrox's compatiblility with tweaked VGA games (not just EGA) is less than ideal, I can understand the argument that the better quality RAMDAC makes up for it.
With Duke Nukem 3D, there has been a complaint about screen tearing with the Matrox, but I don't know how severe the issue is.
The great thing about the Voodoo 1 is that you don't need to fiddle with environment variables or dlls as you would on the Voodoo 2 for some DOS and early Windows Glide games, they just run with the card. Sadly, the resolution (640x480 with Z-buffering) and the performance ceiling are far more limiting than a Voodoo 2 or later.
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