Most AT power supplies have a switch on the back to set it to 110V.

I have no experience with the Athena power supply, I'm using known brand ATX power supplies (Corsair CX450M) with an adapter.

Thanks florian3. Sadly, this PSU doesn't have that option.

Question, can you share a link to your adapter? Also what did you use for the power button?

I have one of these these. You can use the existing power button of an AT case.

However ATX power supplies are also not perfect. They don't have -5V that some old ISA cards need (most don't). The PSU fan location may be suboptimal for some cases. And most only output ~20A on the 5V rail.

Thanks for the info. It also looks like the adaptor you linked is a 2pin where i have a 4pin AT Push Button. That said, i think the Athena on Amazon is looking pretty good for a direct replacement.
https://www.amazon.com/dp/B0042P2IIG/?coliid= … lv_ov_lig_dp_it

I've been using the Athena 400W PSU from Amazon for awhile now with an MMX 233 machine. I haven't had any problems with it so far.

That's awesome news.. going to move forward with one now. Thanks all.

I wouldn't rule out the modification option.

By default, 220V voltage power supply units can be modified for the 110V electrical system just by installing a single jumper wire. 220V-only PSUs often have unused 115/230V switch solder pads marked on the PCB as "SW" that need to be connected. From a schematic point of view - one of the AC lines must be connected to the center point of the two filter capacitors, which go right after the bridge rectifier.
That's about it, perhaps only a fuse should be adjusted for the higher current.

I noticed that athena AT-AP30 has 30A on the 5V and 30A on the 12V rail. What about 3.3V? There is none?
Now I have absolutely no clue about electrical stuff, so probably this is a dumb question but I do own alot of old PCs that could use a PSU like that!

In modern PSUs, +3.3v is usually shared with +5V (i.e. converted from 5v rail), but AT standard has only 2 major rails - +12v and +5v, so that's not a problem. Also, practically none of the systems which may require 30A +5V were built for AT standard. Tthat problem is overblown out of proportion, just as lack of -5V rail.

So any decent modern ATX PSU (better noise floor, internal temps, ripple suppression, protection and modular cables to avoid clutter) with an adapter should be preferable .

So it’s safe to use this psu…thanks for the info!

Kouwes wrote on 2023-04-19, 20:00:

So it’s safe to use this psu…thanks for the info!

I used the Athena Power AP-AT30 and it works like a champ. No mods needed, just plug-n-play for the most part. Read the reviews and you'll see some are saying the cables are to short. I have a mini tower and they are just fine.

https://www.amazon.com/Athena-Power-AP-AT30-S … ps%2C124&sr=8-2