Hi,
I found something new. DOS Glide games won't run anyway on my system. Having a SLI is the red herring, I removed one card, and discovered that I have to slow down the cpu to run older games.
There's a Pentium III 533B and a MS6199VA with Apollo Pro 133 (693A) chipset in here.
Found some info here:
Voodoo 2 difficulties.
I tried pciset but i have to find the device id of my chipset.
EDIT: Looks like the vendor/device id in the fixap133.bat file are the same as those I found with System Information Viever. When I run it, nothing seems to change. Tomb Raider 1 starts sometimes and hangs when drawing the first frame. You can actually see a faded half of the first frame drawed on the display, sometimes a bit less, and sometimes nothing at all, in many cases followed by a beep of the pc speaker.
Carmageddon and Splat Pack won't run at all. I noticed that this is happening both with the cpu running at full speed or slowed down to 400mhz.
I first tried this Voodoo2 SLI setup about 3 years ago with an ASUS P5A motherboard and AMD K6-2, but it was not detected, then I switched to MSI and P3, in this way the SLI was detected but older glide games, which were running fine on the former setup, weren't working anymore. I haven't turned on that machine in a very long time, and this is why I assumed that SLI was the culprit, but apparently I was wrong.