Can you give other examples of boards that can use your upgrade module?

I have ordered already something exotic that probably has the same layout.
I do not want to throw spoilers at people. I will make a video about that.
Either-way for me it is very simple to modify the adapter and reorder.

I remember when I was younger I had always heard about how there existed 386SX systems with removeable CPUs. I would often rummage through junk bins in used computers stores looking for such a motherboard. This was before eBay listings had many pictures, and search engines didn't have an image search, so the ability to locate such things was extremely limited.
Even today, finding such a board is rare. From what I can tell, the majority of boards configured this way were in OEM systems. Every time I find a board like this on eBay, I try to document it. Needless to say, I haven't found too many. But during my searches, I occasionally noticed a 386SX board with solder pads for what looked like a test socket...but the pinout never seemed to be very consistent.
One day over 15 years ago I managed to purchase several desoldered 386 QFP100 test sockets that had a staggered pinout. I searched for a long time for a board that I could solder one onto. I think in all my searching I only ever found 1 or 2 boards that looked like they might accept my sockets, but I think both of them were very old and not worthwhile.
There are at least 4 or 5 pinouts for 386SX test sockets that I am aware of. They all seem to be about equally uncommon. I think I may have seen the one on your M396 on perhaps one other board. The most common one I run into is used by the military grade 386SX in PGA, which is also extremely rare.

DTK 386sx systems came in a socketed cpu version

whaka wrote on 2022-05-02, 20:00:

ohhh i realize i didn't put my contribution here. i successfully upgraded 2 PS/2's with SXLC2 50 and 40 Mhz chip. […]
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ohhh i realize i didn't put my contribution here.
i successfully upgraded 2 PS/2's with SXLC2 50 and 40 Mhz chip.

first is a model 35 (isa) originally with a SX20, successfully upgraded with the SXLC2 50 G50 (without 3,3v mod) , overclocked to 33 MHz. and for bonus, cache is enabled by bios.
and clock doubling work with software control, and 66 MHz is possible totally reliably. but i added a heatsink, clock doubling also mean heat doubling 😀.

second is a model 55SX (mca) originally SX16, successfully upgraded with the 40 Mhz (so real 5V part) , tried overclock to 20 MHz but fail. cache is enabled by bios.
clock doubling doesn't work, the machine crash. don't kno

- model 55SX
hi, i'm also modifying an ibm 55sx by mounting a 486-50 processor.. i wanted to ask.. how far can i put the quartz of the clock without the system exploding?!?!?!?

hi, i'm also modifying an ibm 55sx by mounting a 486-50 processor.. i wanted to ask.. how far can i put the quartz of the clock without the system exploding?!?!?!?

The timing test in the BIOS fails on a 55SX for any speed crystal above ~18Mhz... i.e. it complains and won't boot.

edit: for clarity, it's a double speed crystal, that means you can't replace the 32Mhz with a 40Mhz, but a 36 might be okay and a 38 is a coin flip depending how warm or cold the system is at boot.

ok.. so I have to put a quartz no higher than 36Mhz.. with the 486 I hope to get some benefit..

even without overclock you'll get a substantial benefit, the cache by itself is already a good improvement.
and as i said it's enabled right at boot 😀

386—>486 build

This is my 386 upgrade thread :p

Curious if anyone else has any ideas why I can’t get clock doubling to work?