Wow that brings back memories, I must have built 1000 machines just like that...
so it looks like a 286 machine with a pirated award bios, 360k floppy drive, Seagate 40meg hard drive with a western digital MFM controller, looks like 640k of ram, 2 banks of 256 and 2 banks of 64 all at 120ns, im sure glad ram still isn't inserted chip by chip anymore, one pin bent under ment pulling them all out one by one trying to find the bad one... The I/O card was the standard, 2 serial ports, a game port and printer port. this machine probably didn't do any serious MODEM action as the UARTS on the board were never upgraded to the 16550 chips that would allow faster thruput for modems over 2400 baud and/or a multitasking OS. and a EGA card, :) probably a game machine! that's high end graphics!
The numbers written on top the hard drive are for when you had to LOW-LEVEL format the drive, you would use DEBUG from DOS prompt and use the command G=c800:5 to start the low level format and you would need the Cylinder / Heads / Sectors per track, this drive could have been pushed to 65 meg with a RLL controller it would have made its data transfer rate go up as well if you got the interleaving correct on the low level format. it probably had a 28ms access time and a transfer rate of 5Mbit/sec the ST-251 was a real junker im surprised it still works. don't worry about that clunking sound when you power it up its totally normal...
Hhahaha upgrading your UARTS on the I/O card I think was like $15 a chip, and throwing in of a RLL drive controller was the Overclocking of yesteryear :)
oh it looks like its 25Mhz and check out the size of the heatsink! ;)
can't think of anything else at the moment,, very cool too see one of those again