sometimes they are picky about the slots. Try a different pci slot and see how it goes. Also try it without any other cards (soundcards etc), it may have a conflict somewhere.

Sadly no. The V1 slows down performance on the main-gfx card, using every other pci slots.
Could it be so, if the V1 is somehow less powerfull than what's it designed for in the first place?

I will test this weekend on a super 7 system and see if the same thing happens on my system.

maybe 3dfx's way to beat the competition? 😎

Will report back...

Might be... 😁

Anyway.
I have had my Rightous3D V1 card in both Socket 478, Slot-1 and SS7 systems, ranging from K6-2 500 to P4 2.8 GhZ.
Well, a lot of different systems actually. All the same issue, with the V1 giving the games a sluggish feel when using the primaery AGP card.
Those cards were as I have written earlier, cards from TNT2-M64 to TNT2-Ultra and up to Radeon 9600.
I even tried Matrox G400 in some systems. All had the same sluggish feel when the Voodoo was in place.

Anyway... I have just gone "wild" with a new build, were the horsepowers outperforms this issue.
Running 3D-Mark-99 on the radeon, the system gives 7424 in 3d-Mark and 29497 in 3d CPU Mark.

The system is:
Asrock P4V88 motherboard (Socket 478)
Intel Celeron 2.26 ghz, 256mb Cache. (Think it is an prescot core)
Two sticks of PC3200 Kingston Value RAM running in dualchannel setup.
Asus Radeon9600 AGP 256 mb ram.
Rightous 3D V1 card.
Sound Blaster Live CT-4620, with the internal midi extension board.

The software is Win98SE and DirectX 9.0C
Drivers are the ones found on asrock's website (the newest ones)
Plus I have updated with the last reference drivers fron 3DfX.
The Live has Live Ware 3.0 installed.

This setup is so powerfull, that it can do my NFS-2000 and UT99 without any sluggishness.
NFS-2000 in 1024x768 in 32bit all maxed out, and UT99 is just running 1024x768 in 16 bit.
(Don't need higher in UT99)

And NFS2-SE runs beatufully in 3DfX mode too at 640x480. 😜

One could argue, that this is not really a true retro build. On the other hand, this system
is just right for high powered Win98SE gaming machine. Running V1 just for the fun of it.