Although I don't have a PCI example, I have two AGP cards which are identical other than some different numbers on the GPU die and only one will work with these "problem" motherboards. The card is fine in other boards but is consistently unrecognized by the BIOS on all systems that have this issue.

Maybe there is a problem with the tolerance on one of the parts that is borderline and it's affecting the timing or some voltage circuitry.

I also have two other TNT Pros for AGP where one is fine but the other will have this problem but only sometimes. Resetting the system a couple times usually gets it working and then it seems to stay working. It has only tantalum capacitors so it's not a dried out electrolytic.

Normally my hobby is setting up and configuring computers, from then on I lose interest and move on to the next one.
Yesterday I started to test the Rage Xl that I have on the computer that I mentioned above and the conclusion is that in terms of performance it is more or less at the level of a voodoo rush, usually a little lower depending on the game, which is what The only one that I have to compare, and in terms of capabilities, it seems that the important thing it lacks is the support for 8-bit palletized textures that were very common at that time. In OpenGL games the performance is uneven since in Quake II it reaches more fps than in Quake. GLQuake is playable but shows graphical errors and significant FPS drops at times while Quake II is playable only with some slowdown. Forsaken is perfectly playable with a minimum of 25 fps and very high maximums, the voodoo rush is slower in general but shows more stability in the fps always between 24 and 30. Turok is also perfectly playable with some errors that seem to have to do with the fog. Redline racer is perfectly playable with bilinear filtering very obvious and annoying bugs
My conclusion is that it is much superior to a Virge but it is not a marvel that allows you to play everything in 640x480 with high detail.
For its price it is a good solution to give 3D capabilities to computers with only PCI taking into account the price of the other alternatives. Finally it leaves me the impression that with a processor superior to the PMMX it would give better results since the drivers that I use, 5.30, which are the only ones that seem to correctly recognize the Rage Xl are from the year 2000, when the PMMX was already old and so much SS7 as slot 1 have AGP that gives more possibilities.
I did all these tests without modifying any of the default settings.
Sorry for my English.
😉

That's some good analysis and I can confirm the problems with GL Quake. You can work around it by using a source port like FitzQuake but this card would have been a real gem if it didn't have all of these minor glitches. I wonder if it's a problem within the silicon that ATI was unable to fix with their drivers.

Besides the advanced 3D features which have problems, it's very fast in DOS and 2D acceleration in Windows appears stable.

Ati seems to be famous for not writing good drivers at the time, it seems very likely that it was a driver problem but I can't find a totally good one. I also tried Turok 2, and if I remember correctly I played it at the time with a PMMX 200 and a Riva TNT without problems, but with this Rage XL it is impossible to play it fluently, it lacks a bit of power. So I tried to overclock it but my card does not overclock well or powerstrip does not recognize it correctly because I have seen a video in which it overclocked to 120 mhz.
As far as features are concerned, it does not lack many important things. I also have a Matrox Mystique 220 and that one lacks a lot of 3D features and is also more expensive to buy than these Rage XL. It remains a very good option since it leaves out a lot of PCI graphics cards that have a totally out of place price, the already mentioned Mystique 220, the s3 trio and virge, also tried a Virge DX to compare and the virge must have the half the power or less than the Rage.

I picked up a genuine ATI Rage XL to see if it provided 3.3V, and I can confirm that it does. The compatibility issue with motherboards seems to be exclusive to the Chinese models, probably as a means to cost reduce the part.

@Kahenraz

You've probably already tested this with the Rage XL variant, but I recall, about 20 years ago, having been able to use a Rage Pro with Windows 3.1 drivers meant for a previous generation Rage card (probably a Rage II).

Btw:

Re: Adding 3.3v to pci (Beta)

For those who don’t have 3.3v here is one way to fix it.