Ozzuneoj wrote on 2023-03-30, 20:21:

pentiumspeed wrote on 2023-03-30, 20:04:

IBM 90 XP is a IML machine that stores bios firmware on hard drive. You need to initialize the hard drive then insert the IML […]
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IBM 90 XP is a IML machine that stores bios firmware on hard drive. You need to initialize the hard drive then insert the IML firmware then proceed with partition and formatting as instructed in the read me.

I can send you my 4MB memory modules enough for 16MB and some left over for your 90 XP as they are propriety and is no use for me. They are correct part.

I had 90 XP once. Unfortunately.

Cheers,

This has all been taken care of throughout the thread and the machine is working fine with proper RAM in it, but thank you anyway.

If I ever found another RAM card to install the SIMMs onto I would probably use that RAM, but as it is I would have no way to use it as I have 24MB installed now.

Fine enough, Just remember these DIMMs I have is no use for me totally. None works in any of mine I have.

Actually, you *do need* the second RAM board to get interleaved memory access working. A and B DIMMs filled two slots at a time, one each to a memory board for set of two.

Cheers,

pentiumspeed wrote on 2023-03-30, 23:52:

Fine enough, Just remember these DIMMs I have is no use for me totally. None works in any of mine I have. […]
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Ozzuneoj wrote on 2023-03-30, 20:21:

pentiumspeed wrote on 2023-03-30, 20:04:

IBM 90 XP is a IML machine that stores bios firmware on hard drive. You need to initialize the hard drive then insert the IML […]
Show full quote

IBM 90 XP is a IML machine that stores bios firmware on hard drive. You need to initialize the hard drive then insert the IML firmware then proceed with partition and formatting as instructed in the read me.

I can send you my 4MB memory modules enough for 16MB and some left over for your 90 XP as they are propriety and is no use for me. They are correct part.

I had 90 XP once. Unfortunately.

Cheers,

This has all been taken care of throughout the thread and the machine is working fine with proper RAM in it, but thank you anyway.

If I ever found another RAM card to install the SIMMs onto I would probably use that RAM, but as it is I would have no way to use it as I have 24MB installed now.

Fine enough, Just remember these DIMMs I have is no use for me totally. None works in any of mine I have.

Actually, you *do need* the second RAM board to get interleaved memory access working. A and B DIMMs filled two slots at a time, one each to a memory board for set of two.

Cheers,

If you're giving them away I'd gladly take them just in case I ever find another memory riser.

However, that information about memory interleaving does not apply to the model 90. It appears that the Model 90 and Model 95 are completely opposite in this regard:
https://ardent-tool.com/90/Planar.html

"for interleaved configuration, you place matched speed/size SIMMs in A1-B1, A2-B2, and so on. Please note that the SIMM pairs do NOT cross between memory risers. The Model 95 uses separate A and B banks (A1, A2, A3, A4 then B1, B2, B3, B4) while the Model 90 uses both banks on both cards, A1, A2, B1, B2 then A3, A4, B3, B4)."

As for the memory, IBM used presence detect, so not any parity module will work, but they can be converted easily.
http://mcamafia.de/mcapage0/memorypd.htm
Often just a solder blob is used, or a 0 Ohm smd resistor. I even own some with miniature switches to adjust the presence detect.

Ethernet is hard to find and expensive if found, especially the 10/100 Olicom MCA.
Sound for MCA is even rarer and even more expensive.
Using some kind of parallel sound adapter may be a solution.
I suggest TR as it is much cheaper, more authentic for old IBM systems and really cool after you understood the basics.
For TR you will need some kind of hub, switch or concentrator (e.g. an IBM 8228) as there is no back to back mode like a crossover cable for ethernet.