If you're not going to run your graphics card at 50MHz 0WS, then don't even bother. Fast graphics are probably the only real benefit you're going to see at 50MHz, since your main memory and cache will require extra waitstates yielding performance similar to an optimally tuned 33MHz system if you're lucky.
From my own experience and from what I've read over the years, it seems that very few VRAM based cards will work at 50MHz 0WS. Your best bet is to use something DRAM based with as late a production date as possible. 45ns DRAMs on the graphics card are probably also a good idea. I also heard that soldered in memory is more tolerant than memory installed in sockets.
The two cards I own that work well at 50MHz are a Hercules Dynamite Power with ET4000W32i, and ARK1000VL. My ARK actually seems to work at 60ns OWS, even with 60ns RAM. Other cards to consider would be Trident TVGA 9440, S3 864/868, CL GD542x, and similar. Not sure how stuff like Trio64, CL GD5434 and other highly integrated chips work, but my impression is that they may top out at 40.
Taking your drive controller off VLB is probably also a good idea, since VLB 1.0 doesn't even officially support 1 slotted card at 50MHz, much less two.
"Will the highways on the internets become more few?" -Gee Dubya
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