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Re: Supercomputing adventures with a MegaST/4
Posted: 04 Sep 2026 19:11
by dml
One problem with this is the connector is a big unobtanium thing with metal teeth and a bit too big to solder directly at normal temperatures, without also starting to burn the wire insulation as the copper strands sink the heat very fast.
power-conn.jpg
I decided to use indium-tin solder which melts around 150'c and I was able to keep the iron under 200'c and still make a decent joint.
There will be 3 current-carrying wires for +5V/GND each and two smaller sense wires for feedback, carrying no current.
soldered-power.jpg
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 09:55
by dml
This morning, power issues have become a historic footnote in the journey of
>> The Atari Compute Surface <<
(e-waste coffee table edition - case & overall safety not included).
we-have-the-power.jpg
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 10:18
by exxos
Its a real project now its got wires dropped over everywhere :P
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 10:38
by dml
exxos wrote: 05 Sep 2026 10:18
Its a real project now its got wires dropped over everywhere :P
I do like my spaghetti wires :thumbup:
It's impossible to move now of course because of the short chonky cables but it'll be fine for the next few steps.
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 10:57
by dml
....just making sure it all still works after my bodges.
retest.jpg
:dualthumbup:
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 10:58
by dml
....lets add one more....
four.jpg
four-test.jpg
Well that last bit was the easiest bit so far!
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 10:59
by dml
...lets add four more...
eight.jpg
eight-test.jpg
:yay2:
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 12:07
by Steve
Amazing! Congrats! That's far more power than the original Atari ATW800 ever had!
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 12:10
by exxos
That's gonna be some good pixel rendering power for sure!
Re: Supercomputing adventures with a MegaST/4
Posted: 05 Sep 2026 12:43
by dml
exxos wrote: 05 Sep 2026 12:10
That's gonna be some good pixel rendering power for sure!
Yep, can't wait to get it doing something interesting...
Each one of these has 4MB of DRAM onboard and 4k of single-cycle SRAM. They also have a FPU each.
So if you include two inside the case (I have one removed because the 2nd slot bumps into the RTC battery holder with the lid on), that's ten FPUs available to the MegaST :P
The T800s on the carrier are only 20MHz but I might be able to hack them up to 25 later.