Subscribe via RSS

Compaq Deskpro 386s/20n: More RAM

This has been a challenge. The user manual only really indicates the spare-part numbers for modules, but searching for those proved difficult. Therefore I went in for the lucky dip and purchased whatever I could find on eBay.


First was a cheap batch of unknown SIMMs. They all turned out not to work. I then purchased 2x4mb EDO SIMMs specifically by Compaq, but they didn't work either. There's a few FPM SIMMs below that should work... maybe they've been damaged by static or are of the wrong spec. Seems like I need compaq-certified FPM and hopefully I've now ordered the right parts.

Here's what I've got, what worked and what didn't. I've used the DRAM info page at retro hardware to try and determine the module information.

Update: There's a link here at efetcher that indicates I need parity RAM.

Module details Chip details Status
Original 2mb SIMM
(256kbit x 4) x 16 = 1mbit x 16 = 8MB x 2 = 2mbyte
KM44C256BJ-8 (x16)
KM41C256J-8 (x8)
Works - 2mb
DSC06638 DSC06639
Compaq 2x4mb EDO SIMMs Compaq 185173-002 - EDO - 4MB
Fujitsu 814405C - 60
9269 F98 (8 chips)
Does not work
DSC06640 DSC06641
Could be SMART CQ SM5321000W-7
1mbit x 16 = 2mbyte x 2 chips = 4MB
JC - 70
9545A KOREA (2 chips)
Does not work
DSC06539 DSC06540
4MB DRAM Singapore TM248GBK32U-60 9706
TM5418169DX (4 chips)
Does not work
DSC06533 DSC06534
4M bit dynamic RAM organized 1,048,576 x 4-bit
4mbit x 8 chips = 8mbit (1MB) x 4 chips = 4MB
Maybe EDO?
J - 70
9512B KOREA (8 chips)
Does not work
DSC06531 DSC06532
Another 4MB FPM?
ABORL1 - 6 (8 chips)
Does not work
DSC06537 DSC06538
4M bit dynamic RAM organized 1,048,576 x 4-bit
Officially EDO.
16 chips = 8mb.
SEIWA - Made in Japan
LJ - 60
9461C KOREA (16 chips)
Does not work
DSC06535 DSC06536
4M bit dynamic RAM organized 1,048,576 x 4-bit
Officially EDO.
16 chips = 8mb.
4mb 72-pinn PARITY SIMMs WORKS! - 8mb
DSC09117 DSC09119

The machine simply does not turn on when it doesn't like the RAM... no beeping, nothing. Will report back when the FPM parity RAM arrives.