Motherboard says "SN 901013" on it. I didn't get any relevant hits with a quick google search though.
Cache check didn't see the cache when run on default settings.
Over in this topic Register settings for various CPUs it is said that "The DLC/SXL chips have L1 cache enabled by default, however the whole 4 GB memory region is set as non-cacheable [by default], which doesn't allow for operation of the L1 internal cache. Use -i1 to inhibit region 1, thereby making this region cacheable." (with -i1 being an option in a particular cyrix configuration program). Utilizing this on my end gives me the result that cache check sees that the cache exists and games/benchmark programs get a noticeable speed boost. I'm basically going from 6FPS in superscape benchmark in default settings to ~12 FPS with the cache enabled.
CPUcheck in Phil's benchmarks gives speed as 49.7MHz. Cache check in Phil's benchmarks says 486 at 56.7MHz. HWinfo correctly identifies the processor name and speed as 50MHz.
With the cache enabled, shareware games run mostly as I remember. Apogee/ID/Epic stuff is mostly smooth and playable if not full speed, especially with detail settings turned low for those games that have customizable graphics options. I was very pleased to find out Jazz Jackrabbit and OMF 2097 are in the playable bucket with the cache enabled, I certainly remember playing them on the machine without thinking they were slow, even though I've seen in some places that people regard them as too demanding for 386s. A few more complicated games run slower than I remember (Mortal Kombat 2, Doom, Blakestone), but that might be rose colored glasses thinking they ever ran better than they do now. All in all, with the benchmark and info programs correctly identifying the clock speed and cache, I must be essentially at the optimum settings for this old 386, though I'd love to stumble on some esoteric setting that gives me a little more juice (for instance, the cyrix utilities have options for enabling/disabling barb, a20 and ken inputs and I don't really know what that means or if it would do anything on my machine, but might as well flip the switches and see if they do anything, right?)
Still have more plans for this machine on the software side, like installing Win 3.1, and getting the CD drive and a soundcard going.