When i google `` voodoo3 fic 2013`` i find multiple posts about fried boards and fried voodoo3`s (probably whichever goes first). All posts were from the time these boards were new.
Seems to be a problem with the board with supplying power to the agp slot. Older types of boards use regulators up to 2,5A (2,5a x 3,3v = 8,25w max!)
Newer boards us 6a regulators so they can provide up to 19,8w max.
Voodoo3 pci seems to work without problems. Somewhere there was a link to the fic site where it was even mentioned but unfortunately that link was dead.
Since the voodoo3 is a 15w part (max) i think you can rule out a lot of cards and using pci is probably the best thing to do with that board.
Safe bet for agp on such a board is geforce2 mx (4-5 watts only)
I can`t find anything about the power draw of a TNT2 but i think you are pushing it when you know it`s successor (geforce 1) was using 18w.
Some said that revisions later than 2.0 were better and v3`s would not get fried (newer power regulator). Also early revisions before 2.0 can not support k6-2 450mhz or higher and don`t support k6-3 cpu`s.
asus tx97-e, 233mmx, voodoo1, s3 virge ,sb16
asus p5a, k6-3+ @ 550mhz, voodoo2 12mb sli, gf2 gts, awe32
asus p3b-f, p3-700, voodoo3 3500TV agp, awe64
asus tusl2-c, p3-S 1,4ghz, voodoo5 5500, live!
asus a7n8x DL, barton cpu, 6800ultra, Voodoo3 pci, audigy1