Something like 10 Video cards under the same definition as VDU, not necessarily graphics cards because a couple of them are mono text. Probably 20+ "VGA" cards capable of VGA and 30 or so GPUs capable of 3D acceleration (of which 4 or 5 are not also VGA cards because they don't have 2D output)
Let's see what I remember
2xMDA IBM with parallel.
1x IBM CGA
1xHerc/mono mini
1x Graphics wonder,
1x offbrand EGA
1x MDA/CGA/EGA 2nd tier manufacturer not recalling.
1x EGA Wonder
Okay that's only 8 I guess, maybe more around.
1x VGA wonder
2x some oak/WD crap
4-6 TVGA8900
2x TVGA9000
1x Mach 32
1x Mach 64
3x GL5429
1xGL5434
1xGL5430 PCI
2 x TGUI 9680
2x basic trio
thinking there's another 2 PCI 2D one or two MB that aren't S3, CL or Trident but can't bring them to mind.
Then 3D
Virge GX 4MB
2x Riva128
2xRage II crappy
2 or 3 Rage II okay-er, pluses or C rev.
2 Rage XC/XL
2 rage pro
1 Permedia 2
1 Number 9 revolution IV
1 Rendition verite
1 i740
3 SiS 6326
3 Rage 128
2 Power VR 3dx Apocalypse (no 2D)
2 V2 12MB
1 voodoo banshee
1 v3 PCI
2 TNT2
2 riva tnt
1 GF1 ??
2 GF2MX400
2 GF3
2 GF4 TI4200
2x Radeon 7000ish
1x Radeon 7500
Hiding on me, not recently confirmed are some dualhead matrox g200?? ti4600 which I think had issues, 2 V3 3000 AGP, 1 V3 PCI, 1 Diamond Monster 3DII 8MB, possibly a TTR-II, GF8800
2x Rad 8500
2x 9000 series
2x 9600 series
3x GF6200 PCI
1x 7400GT PCIe
1x7600
1x7900GS
1x9400GT
3x9600GT
1x gt280 in pieces, might try reflow
3x x300/600 series
1x HD2600
2x HD3450
1x HD4650
2x HD4870
1x5830
2x5850
2x6450
2x6850
3?x 6870
SiS Xabre 200
SiS 315
and some newer stuff I dunno.
Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.