my 486 baby-AT board is in a micro-atx case - just bought a blank io shield to cut a hole for keyboard connector and cut holes to mount serial ports in.
Drilled holes in the right places for standoffs in the motherboard try.

I had 3 cards and then used the last slot to mount a CF-IDE backplate so didnt need to cut out an extra panel.

Works well

squelch41 wrote on 2021-02-10, 21:06:

Works well

How did you do the power? Did you refit the case for an AT power switch or did you use an ATX power with adapter and use the existing power switch?

douglar wrote on 2021-02-11, 00:21:

squelch41 wrote on 2021-02-10, 21:06:

Works well

How did you do the power? Did you refit the case for an AT power switch or did you use an ATX power with adapter and use the existing power switch?

I used an atx supply with an atx-at adapter. Swapped out the switch in the case button from a momentary switch to a latched switch (just measured the actual switching bit under the case button and went to ebay) and that connects the pins you need to start up the atx supply (+ no mains voltage running through the case!)

Hey folks, I've been doing this for a while with my 3d printed adapters, I posted about it in a retro stuff thread but it should really have had a dedicated thread.
You can see pictures of my adapters here: Re: Bought these (retro) hardware today
On my 486 case, I bought it specially because I could see that unlike the Inwin cases (of which I have a few), the standoffs could just be unscrewed, so adapters could sit much lower with no risk of screws causing shorts. But my 386 build has pressed in standoffs and works great.

The files can be had here if you've got a 3d printer handy: download/file.php?id=92248
Then you can make some adapters that sit the motherboard 3 or 4mm higher (with a similar riser for the card slots) without needing drilling. Personally I print them in PETG since PLA can warp at quite low temperatures.
This includes:

• The backplate for ATX > AT with that micro ATX position
• An adapter to raise up the card slots mounting surface (needs longer screws)
• Front & back mATX to AT adapters.

Beware that the adapter bracket screws attaching to the original standoff locations might be very close to the back of the board. Use small countersunk screws which are available on ebay etc, search for hot swap caddy screws (UNC 6/32 countersunk). Or put insulation on top of the screws.

For the ATX power, I just use TFX or SFX power supplies with an AT > ATX adapter, sometimes with a -5v adapter modded in. My power switch also is just converted from a regular momentary switch to a latching switch. With that said though, my 486 didn't even get a power button, its power supply has a switch on the back so I just use that, like my old XT case 😁

Thanks for the info. I appreciate it!

could work yes, and no need to add extra slots, the top 2 slots you'd loose could easily be used for things like I/O Cards, wouldn't work well on an AGP system but for everything else it should fine.

Thermalwrong wrote on 2021-02-12, 22:39:

Hey folks, I've been doing this for a while with my 3d printed adapters, I posted about it in a retro stuff thread but it should […]
Show full quote

Hey folks, I've been doing this for a while with my 3d printed adapters, I posted about it in a retro stuff thread but it should really have had a dedicated thread.
You can see pictures of my adapters here: Re: Bought these (retro) hardware today
On my 486 case, I bought it specially because I could see that unlike the Inwin cases (of which I have a few), the standoffs could just be unscrewed, so adapters could sit much lower with no risk of screws causing shorts. But my 386 build has pressed in standoffs and works great.

The files can be had here if you've got a 3d printer handy: download/file.php?id=92248
Then you can make some adapters that sit the motherboard 3 or 4mm higher (with a similar riser for the card slots) without needing drilling. Personally I print them in PETG since PLA can warp at quite low temperatures.
This includes:

• The backplate for ATX > AT with that micro ATX position
• An adapter to raise up the card slots mounting surface (needs longer screws)
• Front & back mATX to AT adapters.

Beware that the adapter bracket screws attaching to the original standoff locations might be very close to the back of the board. Use small countersunk screws which are available on ebay etc, search for hot swap caddy screws (UNC 6/32 countersunk). Or put insulation on top of the screws.

For the ATX power, I just use TFX or SFX power supplies with an AT > ATX adapter, sometimes with a -5v adapter modded in. My power switch also is just converted from a regular momentary switch to a latching switch. With that said though, my 486 didn't even get a power button, its power supply has a switch on the back so I just use that, like my old XT case 😁

Just a word of warning with regards to shorting the power on signal on an ATX power supply and powering it on via the switch on the PSU - I've killed a motherboard, two S3 ViRGE cards and a Sound Blaster 16 by doing this. I can only assume this was due to the quality of the motherboard, but still, would not recommend.

Thanks for the warning, if that happened to you, perhaps I should rig up a proper power switch for it after all. The PSU I'm using on that PC isn't exactly high quality, so I'll definitely consider it.

a low quality psu can maybe send certain inrush spikes into your hardware before regulation has fully kicked in... doesn't sound too far fetched imho, so yeah better be safe.
but in general I would try to stick to high quality PSUs anyways.

Mine is a 5 slot baby AT mobo, so the AGP is the only slot facing a wall, but the AGP slot comes out pretty close to the existing serial port opening, so I'm going to see what I can do with a Dremel when I get a chance. I'm also going to get a 6-32 tap to see what I can do for posts.

I find lots of micro ATX cases in good shape and some full size ATX cases which I need for the full size ATX boards, but the baby AT cases don't show up very often any more.

douglar wrote on 2021-02-13, 03:38:

I find lots of micro ATX cases in good shape and some full size ATX cases which I need for the full size ATX boards, but the baby AT cases don't show up very often any more.

Yeah, that's why I went with a mATX case - AT cases not too easy to come across and prices on ebay, esp with shipping, just more than a period correct case is worth to me!