I have a pretty boring 3Dfx collection compared to a lot of the other people on here...

Just a Voodoo 3 2000 AGP (Purchased new! Used this for a while in the early 2000s before storing it for years.) and an unidentified Voodoo 2 (12MB) board pulled out of an old computer given to me by an acquaintance.

Both are now back in service, in ... almost period correct systems 😀

I just have a single Voodoo3 2000 AGP which I bought second-hand way back in 2002. IIRC, I paid around 30 EUR back then (maybe less?) and only got it because I never had a Voodoo card at the height of their popularity and wanted to see how Glide looked in Deus Ex.

I only used that card for a short while and then put it in storage since it was too slow for any modern games of that time period. Now, almost 20 years later, it still works and has become a permanent fixture in one of my retro builds. Currently playing Diablo 2 in Glide mode for the first time and loving how it looks!

1x Voodoo1 (Diamond 3D Monster) - doesn't work

2x Voodoo2 8MB - don't work

2x Voodoo3 3000 AGP - don't work

1x Voodoo3 3500TV - I think it works
I never did test it with drivers or 3D but it doesn't artifact, doesn't lock up, and it came from a lot of ~24 AGP cards where almost all that I did test have been good, so I'm pretty confident in it.

So that's my one and only. But some day I'll try to fix the Voodoo2s and hopefully end up with at least one of those working.
I never had a Voodoo card so I'm anxious to build a system around the 3500, but this just isn't the time (trying to move).

I think I have a total of 4 3dfx cards.

Voodoo 3 3000 AGP
Voodoo 5 5500 PCI (does not work)
and
2 x 8MB Diamond Voodoo II (plus a homemade SLI cable)

2x 4MB Voodoo1 and 1x8MB Voodoo2. I am a DOS gamer, so even the V2 is little overkill.

1 x Diamond Monster 3D (Voodoo1 4MB)
1 x Diamond Monster 3D II (Voodoo2 12MB)
2 x STB V2-1000 (Voodoo2 12MB)
1 x Voodoo3 3000 AGP

All of them working, though I haven't used the V3 in a while.

The Monster 3D II is the same one I bought back in late 1998, it is difficult to describe to someone that didn't live that era how radically the performance and graphic quality improved, games that were completely unplayable pixelated messes suddenly became silky smooth and at higher resolutions!

Unfortunately I spent most of my savings on that V2 and had to skimp on the motherboard, ending up with an atrociously buggy PCChips M747. So about a year after that I upgraded to a Soyo P3 board and bought the V3, which I remember working fine but being really disappointing in terms of performance increase vs. what I had experienced with the V2.

I purchased the V1 and STB V2s brand new several years ago (although in bulk packaging, not boxed) from some russian guy who had a massive stock. The prices back then were really low compared to today's insanity, but at the time I actually hesitated to spend around USD 40 in order to have a matching SLI pair! How times have changed...

Just a few here:
Guillemot Maxi Gamer 3D Voodoo1
Diamond Monster 3D Voodoo1
Diamond Monster Fusion Banshee 16MB AGP
Voodoo3 2000 16MB PCI

I still remember buying the Guillemot for $100 at an Electronics Boutique store. I think it was the same year I bought my AWE64 Value at the same store. I keep the Guillemot (and AWE64) in my socket7 K6/233 paired with whatever 2D card I put. The Monster 3D is in a socket7 build I did for my mom, paired with a 4MB StealthII S220 (Verite). The Banshee and Voodoo3 I found a couple of years ago on a shelf at my mom's house.