exxos's Atari, Amiga & retro forum

You mean these?

https://www.exxosforum.co.uk/atari/store2/#0137

Yes... they seem exactly the same I ordered... I'm still waiting for them, though.

In the meantime, is there somewhere a list of the axial capacitors needed in order to recap this model of mainboard?

-7 = 70ns
-10 = 100ns

... for a standard 8Mhz 68000 Atari ST 100ns is fast enough. Atari use 150ns or 200ns.

jurassicman wrote: 18 Oct 2025 12:13
In the meantime, is there somewhere a list of the axial capacitors needed in order to recap this model of mainboard?

In my experience the ST generally doesn't need recapping, I personally wouldn't worry too much unless you can see capacitors that look like they're leaking or are bulging, I wouldn't bother.

In any event, just read the values off the caps on the board. My personal preference is to go for 105c caps instead of 85c as it means you have a better temperature range from any replacements.

Thanks for your replies... the capacitors look ok but I was wondering if it would have been wise to replace them as I did with those in the PSU.

I had a look online and axial capacitors are a bit more expensive than the radial ones and not so common so probably it would be just a waste of time at the moment... I'll patiently wait for the memory chips... :)

frank.lukas wrote: 18 Oct 2025 21:11 ... for a standard 8Mhz 68000 Atari ST 100ns is fast enough. Atari use 150ns or 200ns.

Are you sure Atari ever used 200ns RAM chips in any ST machine? At least in theory, 200ns RAM chips are not fast enough.

ROM chips 200ns and RAM 150ns I think but I might have mixed something up?

I finally got the chips, I did mount them on the sockets but my system still sees only 512 KB of RAM... Am I missing something?

The R73, R72 and R71 were already populated as the C25, C26, C27 and C28... please help... :)

Here some pictures...






As visible I did replace the Axial C49 capacitor with a Radial one 'cause it seemed a bit swollen. I've been using the computer for two weeks and I haven't had any issues so far so I think it's ok. It passes all tests and I was able to play all games I did try.

As per the RAM speed, as visible in my picture and as you can read here the original chips speed is 100ns like those I did buy.