T1 polygon flicker (z-buffer?)

[Morgan19]

I've had this problem for a few years now, and I'd really like to get it solved so I can some more T1 time in... Basically, the game worked great with my old GF2 Pro but since I installed a GF4 I get many, many instances of polygons cutting into each other, items clipping through walls, etc. With a little bit of research it seems that other people having this problem have pinned it on something to do with the z-buffer, but apart from that I haven't been able to find any further solutions. Does aaaanyone have any idea why I'm having these problems, why it only started happening with the GF4, and what I can do about it?

(This is running T1 with the latest/last patch. The problem has also happened with several version of Dets including now with the 41.09s.)

m19