exxos's Atari, Amiga & retro forum

rubber_jonnie wrote: 26 Sep 2025 17:36

sandord wrote: 26 Sep 2025 17:13 It turned out I had to use Chrome instead of FireFox.

ram6.jpeg
ram5.jpeg
ram4.jpeg
ram3.jpeg
ram2.jpeg
ram1.jpeg

That spacer looks far too thick to me, will it plug in without?

I tried it without the spacer and it didn't seem to make any difference.

sandord wrote: 26 Sep 2025 17:41

rubber_jonnie wrote: 26 Sep 2025 17:36

That spacer looks far too thick to me, will it plug in without?

I tried it without the spacer and it didn't seem to make any difference.

I'd suggest then that your pins are not properly aligned, the socket looks normal.

Can you take a picture of the MMU board at a angle so we can see where the pins are aligning to the socket?

Looks like you have a typical 70789 style board. That's the type I use for testing.

This is mine...

Here are some alignment pictures.

By the way, the outer bracket doesn't fit over the socket, on one edge the bracket is something like 1.5mm too small.

sandord wrote: 26 Sep 2025 18:38 Here are some alignment pictures.

Looks fine to me..

By the way, the outer bracket doesn't fit over the socket, on one edge the bracket is something like 1.5mm too small.

Its because the socket is warped.

Try removing the MMU and inserting it to take a bit of tesnion off then remove the adapter, refit the MMU and try again.

It's possible the socket is warped as suggested by @exxos

rubber_jonnie wrote: 26 Sep 2025 21:12 Try removing the MMU and inserting it to take a bit of tesnion off then remove the adapter, refit the MMU and try again.

Ah yes that's what I did. It's a very tight fit by design.. It has to be. It has to go on straight down as well.. Trying to hook one side on first and then the other actually makes it harder work.. so you have to push the adapter down almost vertically.. Equal on each side because that is the best way to fit, but of course the socket being warped will make this very difficult.

I think I managed to do it! Here's what I did:

• Pull the MMU chip out of the socket (thanks for the suggestion)
• Push the MMU chip half-way back into the socket
• Place the inner bracket on top
• Put the upgrade board on top
• Push the entire stack down until firmly locked in place

The next steps are disabling the old RAM, testing and then removing the old RAM.

Well done.

it 'looks' about right, but I guess that the proof will be once the old RAM is disabled. The old RAM doesn't have to be removed BTW.