MB-8433UUD doesn't have the VIA chipset; it contains the UMC 8881/8886 chipset. Boards contain the UMC 8881/8886 and SiS 496/497 chipsets result in similar performance. I think the SiS had a slight edge on the UMC board for RAM read speed, but it was negligible in my opinion.
The SiS boards seem to have the benefit of working with the Voodoo3, if you're into that kind of thing, while UMC boards won't work with the Voodoo3. The UMC boards do, on the other hand, work with the Voodoo2 just fine.
I prefer boards with double-banked cache as they allow for faster cache timings when using a 40 MHz FSB. For the Biostar, this at least allows for running 256K double-banked, while the MSI board will do 1024K double-banked. While the Biostar board can be modded to work with 1024K double-banked, this board doesn't contain memory buffers and you will be limited by this when trying to squeeze more out of your system. I have an ongoing test matrix for this scenario when using different RAM/cache sizes and different CPus for the fastest possible timings. It also varies by RAM module density.
The Biostar board will work fine with 128 MB FRM sticks. Most of SiS 496 BIOSes allow for a max of 32 MB sticks, except for the 4DPS 1.72+ BIOS.
The Biostar board runs well with a 66 MHz FSB if you can find an agreeable CPU. I've run it with 1024K, 66 MHz, and 128 MB for quite some time, but for greater stability, you must run RAM Read at 2 WS. For this reason, I dropped the cache back down to 256K and run RAM Read at 1 ws with only 64 MB RAM.
I also run a SiS 496-based board with 32MBx4 sticks and a Voodoo3, but I don't play with it nearly as much as the Biostar.
My goal has always been peak performance without compromising system stability. Determining the edge of what is stable can take years because these systems aren't run as an everyday computer anymore. I am confident I've found this peak performance + absolute stability point with my Biostar board with 66 MHz FSB. Everyday night I test out new 3D games on it (early 3D only - 1995-1998). I'd like to try 512K double-banked cache with 1ws Read to squeeze out a little more, but I haven't felt like pulling the MB out of the case yet. I modified another Biostar board which uses only jumpers to swap between 256K, 512K, and 1024K of double-banked cache, that is, rather than soldering the configuration shut.
I do not recommend running any single-banked cache PCI 486 board with a 40 MHz FSB unless you don't mind running it slow.
I did find a branded ALi-based PCI 486 board. I think its brand is Gigabyte. It only has single-banked cache though and the performance was fairly disappointing in comparing to the UMC and SiS alternatives. I also have the PCChips M918, which is also ALi-based and allows for double-banked cache, but after some tests it became clear that the cache infrastructure wasn't designed properly on this board, as if it was build for fake-cache or something. I didn't even notice a cache transition in Speedsys unless I set the RAM speed way low and the cache speed all the way high. The performance of this board was absolute trash. I'd like to obtain a double-banked and branded ALi-based board before I make any final comments on the ALi-chipset though.
What are you trying to setup? What is your objective?
Plan your life wisely, you'll be dead before you know it.