I'm thinking of building a few of these ATX2AT Smart Convertors from here https://x86.fr/atx2at-smart-converter/ I like the idea of the simple adapter cables for known good hardware but feel having something a bit more robust for the weird shit that can happen when powering old hardware may be more beneficial.

The project is open source so could be adapted to suit any PSU and not just AT.

Having looked at the Github there may need to be a bit of tinkering and substitution to get the right parts for it but a good puzzle never scared me.

TrashPanda wrote on 2023-04-16, 07:35:

I'm thinking of building a few of these ATX2AT Smart Convertors from here https://x86.fr/atx2at-smart-converter/ I like the idea of the simple adapter cables for known good hardware but feel having something a bit more robust for the weird shit that can happen when powering old hardware may be more beneficial.

The project is open source so could be adapted to suit any PSU and not just AT.

Having looked at the Github there may need to be a bit of tinkering and substitution to get the right parts for it but a good puzzle never scared me.

I thought they were for sale I remember seeing them pre fully built somewhere I was considering getting one a long time ago but they were $400 or $600 ish

To the OP I mentioned this in the PM but there is also an option to use a "voltage blaster" it's an ISA card that supplies -5 volts but the downside is it uses an available ISA slot that you may or may not have

GabrielKnight123 wrote on 2023-04-22, 11:51:

TrashPanda wrote on 2023-04-16, 07:35:

I'm thinking of building a few of these ATX2AT Smart Convertors from here https://x86.fr/atx2at-smart-converter/ I like the idea of the simple adapter cables for known good hardware but feel having something a bit more robust for the weird shit that can happen when powering old hardware may be more beneficial.

The project is open source so could be adapted to suit any PSU and not just AT.

Having looked at the Github there may need to be a bit of tinkering and substitution to get the right parts for it but a good puzzle never scared me.

I thought they were for sale I remember seeing them pre fully built somewhere I was considering getting one a long time ago but they were $400 or $600 ish

Its possible they were at some point but the project is a couple of years old now, some of the components used originally are no longer available as they have been replaced, I'm looking into how hard it would be to update the plans with replacement components.

I'm about two weeks late to this, but some of the "7805 replacement" switching regulator modules can be configured to output -5V with a +12V input. They need external capacitors and probably don't have the cleanest output, so they aren't quite as convenient as the PCB shown above.

The versions with flying leads instead of PCB pins cost a little more, but you can just solder wires to the pins (and the version with wire leads is still not that expensive).
https://www.digikey.com/en/products/detail/cu … -500-W/11569242
https://www.digikey.com/en/products/detail/cu … 805-500/7350283
(I'm just using CUI as an example - there are equivalents to the PCB mount version that are in stock)

I'm looking to replace the AT psu in my Gateway 2000 P5-75 ("Zappa" board) with a modern ATX psu, but I'm not having much luck (well, any luck) in finding one of the ATX to AT adapters with the dummy load on the 3.3v rail here in the UK. This is my choice on ebay:

https://www.ebay.co.uk/sch/i.html?_from=R40&_ … to+at&_osacat=0

I'll just opt for one of these on ebay from a decent seller and go without the dummy load, unless any of you folks think that's a bad idea?

Just put this on any ATX power supply and be done with it if you need -5V. Works great..
https://github.com/wiretap-retro/ATX--5V-Inline-Adapter