Robin4 wrote on 2020-01-19, 01:03:[...]
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2x Unkown earlier socket 5 motherboards with aladdin chipset. Doesnt not have the i/o on the board (exeption seems to by one COM header?) Dont know the brand. Maybe an industrial embedded board or something?)
Unlikely. At a guess I'd say an Acer OEM board with Aladdin (1) chipset. That's an ancient 1st-gen Pentium chipset, released for the So4 platform. I'm surprised it also does 3.3V - as it must with So5 and a P133 on it, but that's not unprecedented: SiS' 501 also spans both sockets and voltage. Back in the pre-i430FX period, it wasn't so common to have I/O onboard, and boards that had it tended to have afwful CMD-640 chips. This is a very late board for such an old chipset, I see end-of-1995 markings on the chips. That's i430FX territory. I'd have understood it if Acer had been dumping unsold old ALi stock (the "A" in ALi stands for "Acer"), but that M1451 is the newest chip on the board, from week 44 1995. Pretty odd they'd still be making them this late - the Aladdin II (M1511) had been released somewhere in mid 1995 (can't find exact date, but I have a Cypress clock generator datasheet from June 1995 referring to it), which would have completely outclassed this one.
Bottom line: it's a late holdover from the earliest Pentium days, hence no onboard I/O etc. It does support EDO and modestly benefits from it, benchmarks of the So4 M1451 showed it similar in performance to the i430LX, which is better than OPti or SiS So chipsets, but far, far below say an i430FX, even when using asynch cache (as a 1995 board would). So this is a slow curiosity, not some industrial board.
PCI IDE that would work with old PCI 1.x slots might be a challenge, best bet would probably be to go for a PCI SCSI adapter (like that 2940 😉 ) and add an ISA floppy+I/O controller.
Would be interested in benchmarks vs i430FX or similar if you happen to have comparison available.