Reply 35240 of 38336, by alienmannequin
appiah4 wrote on 2020-07-28, 06:37:
Those pictures are really low resolution so it's very hard to say anything about the state of the cards or components, post some […]
Those pictures are really low resolution so it's very hard to say anything about the state of the cards or components, post some high quality high resolution photos.
As for the expansion cards:
MT255S: Sound Commander ISA, keep it. MT0252 chipset and YMF262 (or clone) genuine OPl3 sound card, probably SB Pro compatible, looks like an early ISA card that isn't all that integrated (possibly a noisy card) but that isn't surprising considering the age of the PC, and makes it a more uncommon piece. Someone with more knowledge will probably confirm the capabilities of the MT0252 soon I think.
TVGA9000: Run of the mill, slow ISA VGA but can run in 8-bit slots so that makes it useful if you want VGA output on an XT or something
RAM CARD: I don't know if that's proprietary but it's probably valuable. 4MB ram is quite handily enough for a 386 too.
Appreciate your time: great insight into these pieces. I'll be sure to post some better pictures here once it is dismantled & the damage becomes more apparent. The sound card is in remarkably good condition, given the overall state of the PC (looks like battery explosion + left out to oxidise, although can't find a battery anywhere). Looking forward to cleaning the sound card up and having a play with it.
mkarcher wrote on 2020-07-28, 08:28:
Those RAM CARDs are proprietary Compaq stuff. The Deskpro 386 series used memory cards that could be upgraded with square-shaped piggyback modules. This applies both to the 386s (SX, 16-bit) and 386 (DX, 32bit) series, although they used different cards. It says 4MB on the RAM CARD, so the card itself has 4MB of RAM. I see one upgrade module being installed, so the combination has 5MB at least, more likely 8MB. See https://retroviator.files.wordpress.com/2019/ … -spec-sheet.pdf for part numbers of the original 386s components. The 4MB memory card is Assembly Number 000969, as printed on your card and shown in that document. I have high hope that the upgrade module is 000993, the 4MB module, as upgrading from 4 to 5 MB seems to be useful only in special cases.
That's a fantastic find, thank you for this data sheet. So, it's Compaq-specific. I have the square-shaped piggyback module - there are quite a few numbers on it that are mostly hidden. Have taken more photos of the layout of the board, as well as the oxidation of sorts - haven't done cleaning yet. Wasn't keen to remove the upgrade module yet - looks as if there might be some brittle plastic flathead bolts holding it on, however managed to wedge the camera for a partial shot of the underside.
devius wrote on 2020-07-28, 10:32:
Repairing that Compaq won't be easy. I'd start by checking what works and what doesn't by testing the components individually.
Appreciate your advice. I'll be photo-documenting every step of the disassembly process, and perhaps on the way I can document the journey here - which part of the forum would be appropriate for such a journal?