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Installing an AT Motherboard in an ATX Case

I needed an AT case for this naked 386 AT motherboard and hadn't had much luck searching eBay. Little did I realise that I could put the motherboard into an ATX case with minor effort. All AT cases on eBay were way out of the price range, so I went back to the store that I purchased the power supply from for the Compaq and came back with another bargain!

There seems to be a faceplate missing, but I can't complain since I got it for AUD$20. It didn't come with a power supply, so I chose to use the AT that the motherboard came with. Of course, the first problem (it's still a problem, actually) is that the power switches aren't able to be swapped. ATX uses a 'soft power' switch whereas AT runs the full 240v right up to the mechanical switch to control the power feed. This is still currently hanging out the side of the case.

Mounting the motherboard was easy enough. Turns out that the read plate actually has all the required markings for the AT motherboard spacers!

A bag of goodies was included and I quickly got the motherboard into position.

Before going any further, I realised that I'd not put a new battery on the board yet. I cleaned the remnants of the previously leaky battery and mounted a coin-cell holder.

Once screwed down, everything fit back into the case perfectly.

The majority of front-panel wires were still compatible with the old AT style pinout... I just required a quick google to find information on the AT System panel connector.

Of course, the included I/O Panel doesn't fit an AT motherboard, so there's extra ventilation at the back. There seems to be all sorts of hints online to make your own plate, but nothing off-the-shelf that I could find.

I popped the top off to see if I could mount the power switch but there was no room for it. I'll have to work out a better mount for it, as the current answer is to have it hanging out the rear.

After purchasing a PS/2 to AT-style keyboard converter, I was able to actually boot the thing up! Now to get some software onto it...