Had this motherboard for some time.
It came with 486 socket only and solder pads for 386 CPU.
Today slapped on it a 40MHz rated AMD 386DX from dead motherboard.
Took a moment to figure-out the jumper settings until it lit on 386 hardware path.
Ultimateretro and stason contain incomplete description - RN15 needs to be in the position shown in the picture below.
I examined before other motherboards based on VIA's VT82C481/495 chipset and kind of knew kind what to expect.
Integrated IDE, FDD, COM, LPT which is nice.
Takes any memory modules and L2 cache chips.
Performance is so-so.
The motherboard came with BIOS version 1.4-something.
There is 2.0 available online. No observable difference in performance and stability between them.
DOS interactive graphics (games, benchmarks) run stably at 50MHz but Windows 3.1 and 3D Studio (complex compute) were not fully stable.
For them had to step down to 45MHz.
All BIOS settings on max.
Cirrus Logic GD-5434 video cards didn't work on this board so used ET4000/W32i instead.
What SpeedSys says:
The usual benchmarks, compared against fast DTK-PEM-4036Y:
Overall decent system but there is much better out there.