Better stay away with your dremel from those remaining AT cases (especially if they are IBM prototypes...😉

Aui wrote on 2025-07-04, 11:50:

Better stay away with your dremel from those remaining AT cases (especially if they are IBM prototypes...😉

This. AT cases are scarce now and ATX cases are like shit in a cow pasture. Don't destroy the few remaining AT cases

I disagree - I think its worth modding those cases to give them new life. If you know how to sue dremel and have modding experience, you can mod it and make it reversable.

Nope, @phinix, I definitely disagree with dremel-based modding of AT cases. If you have vintage AT cases, sell them to someone who needs them, and don't cut them up. There are brand new cases with a vintage look, if you want to buy them.

- Alex

I have to agree with the others here... it took me a couple years to find a couple good condition AT cases to build actual AT systems in and it makes me happy to finally have a couple. I wouldn't hack one up for an ATX build when there's an abundance of old ATX cases - many old ATX cases have fun and wacky aesthetics since they were manufactured over various periods in PC history. Translucent blue, funky plastic waves and ripples, oddly shaped buttons, 5.25" bay drive covers, early cooling solutions, etc. I think it's totally possible to make an old school looking build in an ATX case.

Of course it's totally OP's choice to do what they wish with their belongings, and micro ATX in a baby AT case *would* be cool, but I'd rather see a tidy AT build in it instead. ; )

phinix wrote on 2025-07-04, 11:41:

rarely people do AT case with ATX mobo.

How exactly do you imagine it? ATX boards I/o section is significantly bigger than a typical DIN keyboard hole.
You can also see from the vibes that you are pissing people off with those notions

Many years ago I hacked up a small AT case to fit what was called a "flex atx" Gateway branded socket 370 motherboard for a friend.

I think it was a Coppermine P3 and I think had onboard video, can't remember much else.

Bruno128 wrote on 2025-07-11, 05:41:

How exactly do you imagine it? ATX boards I/o section is significantly bigger than a typical DIN keyboard hole.
You can also see from the vibes that you are pissing people off with those notions

I done this quite a few times and its not hard. and let them get pissed off, its not their case and he can do whatever the heck he wants to do to it.

OP in order to do this you will a full size AT case, the kind with pci slots both below and above the AT hole, that is if you don't want to just cut a big old hole in the back of the case 🤣. Its not like AT cases are not all over the place, we have a gaylord of them them at work going to the scrappers every now and then. It funny, everyone in the retro pc community is so entitled they will moan the second anyone scrapped something but if we say come pick it up they no show.

You will need to de-rivet the AT I/O area or pop the spot welds, this is where the ISA/PCI and com/lpt ports screw into. Then rivet a ATX I/O sheet panel into the case from a donor case, I used to buy the sheet metal from Advantech but is was supper pricey so a donor case is your best bet if you can find a early ATX case or can do a little fab work. You may need to drill and tap new motherboard stand offs too or make a custom motherboard tray. I done this is quite a few AT server cases over the years including a old AT ALR server case I still have so if you need some help or tips let me know. if done right you don't need to cut anything and only need to drill a few holes with it being 99% reversible the 1% being the drilled holes.

This also works for PICMG cases as they are more or less AT.

Alternatively you can cut out the whole back side of the case and fab a new rear panel but if you have to ask how to do that then you should one be taking such a project on. I done that on a few one off form factor mid 90s servers cases and LPX cases.
I have also added fan slots, moved motherboard trays around, modded cases to fit dual PSUs, motherboards, painted cases and so on. So if anyone needs case modding advice or help hit me up. I have a wide range of knowledge that a lot of folks in the PC retro or modern would not have when it comes to metal fab and so on.

Post some photos of the case you got and I'll guide you through the conversion if you'd like.