Ok figured out the problem. Windows desktop was set to 32bit mode so Quake 2 was trying to get the Riva128ZX into 32bit mode when initializing. Changing the Windows desktop to 16bit mode and rebooting resolved the issue.

Getting 32.6 FPS on time demo map1 using 3DNow! OpenGL and 1576 with 3DMark99 on a K6-2+ 550 which is a very similar to a Voodoo 2 running on 1x TMU. Very happy!

you are a genious, thx a lot dude!

I m testing a recently bought Elsa Victory Erazor 4MB AGP Riva 128 and neither GL Q1 nor Q2 wanted to run.
After changing Windows desktop to 16 bit, they started.

640x480x16 = 46.7 fps

system: P3-450, 440bx board, 64 MB, 32GB sd-card, Elsa Riva 128 => woooow: no comparison to Permedia 2 AGP card on the same system, running with only 7 fps at the same resolution

eliot_new wrote on 2025-12-23, 18:19:

you are a genious, thx a lot dude! […]
Show full quote

you are a genious, thx a lot dude!

I m testing a recently bought Elsa Victory Erazor 4MB AGP Riva 128 and neither GL Q1 nor Q2 wanted to run.
After changing Windows desktop to 16 bit, they started.

640x480x16 = 46.7 fps

system: P3-450, 440bx board, 64 MB, 32GB sd-card, Elsa Riva 128 => woooow: no comparison to Permedia 2 AGP card on the same system, running with only 7 fps at the same resolution

Glad to help. Very nice FPS too!

Many old and first 3D videocards had 16bit limited@OpenGL or missed OpenGL ICD at all and had MiniGL, like S3 had.
ATi Rage3 has same 16bit only mode for OpenGL, it can do only OpenGL 1.1. 3DMark/Quake can be similar to Riva128.
No other options, like 24 or 32 bit, alaways use 16 bit color desktop for older graphics, that i have learned at Rage Pro.

i810 / i740 also has such limitations at least i remember on linux mesa opengl only worked with 16bit mode back then.