Great ! Yes, many boards have a jumper for the BIOS chip size or type. Can you take a good picture of the full board ?

Yea I'll try to get some better shots, might even draw it out.

Also it dawned on me I've got one side of ram working so I should be able to swap ram one by one to find the duds by removing one good dipp and testing the 18 chips on the other bank one by one.

Found 3 dead dipps, also here is the best my phone can do

Replaced the 3 faulty and now

Great work ! I see 4Mb of ram ! Hope it all works out ok

yes! nice work captain

you're gonna have a badass little 386sx now, that VLSI chipset is quality

Good job tracking down the bad DRAMs.

I used to toss out a lot of SX-16 and SX-20 motherboards in the 90s, but this one is definitely worth keeping due to its novelty of of being a 386SX "tacked onto" a 286 motherboard. You need to install some crappy operating systems to compliment it. I Recommend DOS 4.00 and Windows 3.0.

Anonymous Coward wrote on 2020-07-08, 02:48:

Good job tracking down the bad DRAMs.

I used to toss out a lot of SX-16 and SX-20 motherboards in the 90s, but this one is definitely worth keeping due to its novelty of of being a 386SX "tacked onto" a 286 motherboard. You need to install some crappy operating systems to compliment it. I Recommend DOS 4.00 and Windows 3.0.

My plan was dos 6.22 and win 3.1, though I could with 3.0. the goal is because of how unfamiliar I am with dos, I can use windows to simplify things a bit. My 486 runs 3.11 wfw with calmira.

All it needs now is a gotek and I'm set.

I'm also interested in a 387sx not that it's useful I just want one

Success! Great job, a full blown 4MB ready to go! Finding faulty chips can be a pain, but good job you got them.

Anonymous Coward wrote on 2020-07-08, 02:48:

(...) You need to install some crappy operating systems to compliment it. I Recommend DOS 4.00 and Windows 3.0.

Lets call it the Windows millennium of the nineties :p

With a 386SX I'd go for PC DOS 5.02, it's memory footprint is smaller than 6.22 and the only things you could miss are Defrag and Scandisk. My 286 runs 5.02 and for Scandisk I just use the version that came with Windows 98 (that does work perfectly) and the DOSSHELL is another curiosity.

Oh and PC DOS 5.02 was shipped with interlnk and intersvr to use a null modem or laplink cable for easy data transfer between two old computers, and even use eachothers hard drive.

DOS 3.3 may also cut it, but there are some more limitations.

DOS 4 was quite buggy, but did support some nice features over DOS 3.3 for older systems, like ems drivers and support for floppy disks larger than bios support. I'd skip this one, as most of these features remain in DOS 5.02.

Windows. I'd go for none. Although it may run, it can barely be useful, because of the relative low cpu power.
If you insist to go for Windows, there is Windows 3.1x as most well known before Windows 95. Will not run but crawl.
Windows 3.0 I'd skip. It is the beta version of 3.1 , unfinished in my opinion.
Windows 2 version 386 or Windows 286 may also be some nice curiosity to play with, but these are are not that well supported by other software. Getting drivers can be a challenge for some graphics cards, and a disaster for soundcards (was sound supported at all?)

Windows 3.0 was actually quite good for its day. It brought features to the PC previously only available on Macintosh. Millennium Edition on the other hand brought nothing new to the table. Most people had never heard of it, and those that had it hated it. It was a product that served no purpose and probably shouldn't have been released in the first place. An extra service pack for 98 probably would have done the job. Maybe Windows 3.0 is more comparable to Vista.

Well done wrt sorting out the ram. A version of PCGeos aka GeoWorks could be useful on this spec system. BreadBox Ensemble was the last incarnation.

I recently got this exact motherboard. I saw candle_86 talked about documenting his journey and I would be very interested in it. Mine came with no memory so I've been trying to find it on the retroweb but don't see it.

It does say 386-SX B3.