So while looking through my father's old home office trying to find his desoldering pump, my brother stumbled across a stack of old Nvidia cards, among them a Riva TNT2 M64 as well as a GeForce 2 MX 400 which should effectively max out the 3D hardware in my retro computer given that it is already being bottlenecked by the 500 Mhz Penitum III Katmai CPU inside it.
Unfortunately Pool of Radiance: Ruins of Myth Drannor actually runs worse on the GeForce than it did with my ATI Rage 128 Pro Ultra, as the map scrolling stutters more now than it did before the upgrade. I have next to no experience with Nvidia cards modern or old, so I just went ahead and followed what seems to be the conventional wisdom floating around on VOGONS and installed the Detonator 7.76 drivers that they have hosted there for Windows 98. Tracking down the Linux drivers was actually simpler.
Biggest winners I have observed so far are Tribes 2 and American McGee's Alice.