short answer, yes.
long answer, while 3Dfx said they support the new ADC, they probably won't implement it on the V5s. The new connector requires more power to be drawn by the video card (as if the V5 doesn't draw enough already), and requires ColorSync, which I'm not sure if the V5 supports. Also, designing another PCB and sending it to factory for manufactering and testing is very expensive, so I wouldn't bet on V5s having ADC anytime soon if at all.
The Radeons on the other hand, should/will have ADC support, but having a Rage128Pro in AGP and Radeon in PCI is just wrong...
[This message has been edited by Evangellydonut (edited 08-25-2000).]