More PCB's from PCBway

Had some some old Edos's in the shed I've had for 30 ish years so built a couple of 4mb Simms so now have 10MB installed.

BBZ149 wrote on 2025-11-07, 14:32:

More PCB's from PCBway […]
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More PCB's from PCBway

Had some some old Edos's in the shed I've had for 30 ish years so built a couple of 4mb Simms so now have 10MB installed.

Very beautiful 🤩 congratulations
I follow Alex's channel (BuB), and I saw that he made modules of 16 MB each, however previously he made those of 4 MB, I also recently thought about disassembling some RAM 72 PIN, but I don't know how much is needed, for example for the two SIMM 30 PIN, how many SIMMs do you need (?)

Thanks! not sure if this machine can take 32mb, but I have plenty of spare RAM so might give it a go! 😀

For each 4mb simms you need: 2 of either of these chips:

4M x 4-bit SOJ-24/26 DRAM

TC5117400CSJ, TC5117400BSJ, K4F160411D-B, KM44C4100CK, M5M417400CJ, MCM517400CJ, TMS417400ADJ

BBZ149 wrote on 2025-11-07, 15:31:

Thanks! not sure if this machine can take 32mb, but I have plenty of spare RAM so might give it a go! 😀

Well if you have enough RAM to build two other modules, you could try but what a memory, the 286 and the 386SX, at most reach 16 MB, so if you don't see them, the maximum would be 16 MB.
But there are cards with eight desks, instead of only four, in that case maybe it could reach 32 MB.

BBZ149 wrote on 2025-11-07, 15:36:

For each 4mb simms you need: 2 of either of these chips:

4M x 4-bit SOJ-24/26 DRAM

TC5117400CSJ, TC5117400BSJ, K4F160411D-B, KM44C4100CK, M5M417400CJ, MCM517400CJ, TMS417400ADJ

Thank you so much ☺️
I'll see if I can find something unusable, that has the same chips as those on your list.
I hope the cost of new PCBs (including shipping) is not high.

BBZ149 wrote on 2025-11-07, 15:31:

Thanks! not sure if this machine can take 32mb, but I have plenty of spare RAM so might give it a go! 😀

10MB is the maximum for that board. (16 is usually the maximum for 286 and 386SX)

AlaricD wrote on 2025-11-07, 16:44:

BBZ149 wrote on 2025-11-07, 15:31:

Thanks! not sure if this machine can take 32mb, but I have plenty of spare RAM so might give it a go! 😀

10MB is the maximum for that board. (16 is usually the maximum for 286 and 386SX)

Thought so! Think I will just leave this machine as it is apart from upgrading the Video RAM with a couple of M514256A-10R as it's only a 386 ill use for dos and Win 3.11, and I have other machines a bit more worthy for retro gaming!

PC@LIVE wrote on 2025-11-07, 16:21:

I hope the cost of new PCBs (including shipping) is not high.

Boards from PCBway were very cheap! Think I paid $9 shipped as chose the cheapest shipping and still came in around a week. Always worth checking the price difference if you just order 5 boards compared to 10 as there is only a minor difference in price!

BBZ149 wrote on 2025-11-11, 23:58:

PC@LIVE wrote on 2025-11-07, 16:21:

I hope the cost of new PCBs (including shipping) is not high.

Boards from PCBway were very cheap! Think I paid $9 shipped as chose the cheapest shipping and still came in around a week. Always worth checking the price difference if you just order 5 boards compared to 10 as there is only a minor difference in price!

Thank you very much friend.
Well right now I was looking for 72 PIN RAM, to pick up the chips and put them in the 30 PIN RAM.
So far I haven't found much, the few I find cost a little too much, I'll try to find a batch of those RAM ones, at a reasonably fair price.
As soon as I have what I need, I could do the transplant, but first I have to get the PCBs, but maybe if there is not much difference, I would order 20 instead of 10, because I could get 5 groups of 4 RAM, which I could use on two PCs 486 (16!) And the remaining 4 on a 386SX.