Here's another rescued, revived and (eventually) restored computer. This was originally a DTK Computer Peer 1630 personal computer with a 386SX-16 microprocessor on a DTK motherboard. It appears to have been built in 1991. Around 1993, someone replaced the motherboard with one having a faster Am386SX processor clocked at 40MHz. I suspect they were going for a cheap performance boost.
The Am386SX processor has all the limitations of the Intel 386SX (16MB RAM limit, 16/24 bit data/address bus, needing two external 16-bit cycles for one 32-bit operation) with a faster clock speed. Despite the "hampered" design, it still would have given somewhat improved performance.
I've found evidence that suggests the replacement motherboard was offered in various speeds. A 33MHz version also exists. Surprisingly, considering that the CPU is soldered, the clock crystal is socketed.
DTK Computer produced motherboards, various expansion cards, desktop PCs and servers from the beginnings of the PC clone era all the way up to the Pentium 4. They're still around in some capacity, though I have no idea if they still make computers or not. Interestingly, the local library has a few other DTK systems, including an early Pentium machine that is still in use at the front desk.
This computer's FCC ID number is F82-5K4PEER1630, granted in late 1989. Identifying numbers on the motherboard include TK83305P9 and TK83305P9-4N-D-02. Neither one produces too many results in a web search.
Remember: If you care about your old computers, make sure none of them have a potentially bad and leaky NiCad CMOS battery in place! Remove it before it harms your old computer. Also consider removing button cell batteries from old computers, or replacing them with new ones. Though it is a lot less likely, I have definitely seen dead or damaged button cell batteries leak and make a mess in old computers.