There are some metrics for this chipset with a Am386DX-40 on Phil's VGA benchmark spreadsheet: Phil's Ultimate VGA Benchmark Database Project

13.9fps 3DBench
3.6fps PCP Bench
6.7fps Doom (presuming that high detail timedemo3)

That puts it at the lower-middle range of results, but, in terms of performance per KB of cache (compared to the other 64KB and 128KB boards around it), it's not bad.

Good call, megatron-uk! I actually downloaded Phil's VGA benchmark spreadsheet some time ago, but I didn't think to check it. 😀
Well, that performance is good enough for me, so I'm gonna go ahead and buy it. 😀 Once I have it in my possession and manage to test it I'll write my conclusions on this thread (just in case anyone else has the same dilemma in the future 😀 )
Thank you!

So, I got the board, it's a very decent performer (not the best, but definitely not the worst). It's also very stable, have been playing with it for the past week and have had no issues. Unfortunately, there isn't much that can be fine tuned further in order to increase performance... There are memory wait states that can be decreased in the BIOS advanced options, however any decrease results in a failed boot / graphical glitches (even with 60ns 30 PIN FPM memory). I'm guessing this is caused by the 40 MHz clock speed.
It still had the original battery which, amazingly, was able to hold a charge just fine. It looks like it was just starting to leak, though, so the timing was perfect. There was almost no corrosion (except just a tiny bit on one of the battery solder pads).
I removed the battery, got rid of the corrosion with a tissue soaked in white vinegar, cleaned the solder pads with a wick, reapplied fresh solder and finally cleaned the battery area with IPA.

It's unclear what board this is (although, it might be a BIOSTAR, because it looks very similar to the one in this thread). Mine has a soldered AMD 386 DX-40 (and it also supports an external 386 / 486DLC CPU).
J3 seems to be a connector for the external battery, but haven't tested it yet (the board works just fine without a battery).

All in all, the Macronix chipset looks like a solid chipset and those 8 KB of cache don't seem to cause any major bottlenecks. Some pics:

And some Benchmarks:

When it boots it shows a long string at the bottom, if there is 001223 in there this is also a Biostar board.

You can make a backup of the bios with this:
http://cd.textfiles.com/microhaus/mhblackbox3 … MORY/GETROM.ZIP

I have a similar board. The main difference the 386 is socketed. I replaced the 386DX/40 with a 486DLC/40 and that made a huge difference in performance. Norton SI is now 65.3 and 3DBench comes in at 20.8 FPS. Here is original post on my 386 motherboard.

Need help identifying 386/40 motherboard

evasive wrote on 2021-05-28, 06:39:

When it boots it shows a long string at the bottom, if there is 001223 in there this is also a Biostar board.

You can make a backup of the bios with this:
http://cd.textfiles.com/microhaus/mhblackbox3 … MORY/GETROM.ZIP

Will do next time I test it. Unfortunately, it's already in storage now...