Hardware Requirements
A/UX was designed for the legacy Macintosh (those based on the Motorola 680x0 line of processors), and was never ported to the PowerPC. If you're trying to install on a PowerPC, stop now... It will not work. Similarly, none of the PowerBooks, LC's, or AV Macs are supported. A/UX bypasses the Macintosh Toolbox, and communicates directly with the hardware, so changing the gestalt (system ID code) will not let you install on an unsupported model. As of 2021 there are two emulator capable of running A/UX: Shoebill - which runs A/UX 0.7 through 3.1.1 Qemu - emulating Quadra 800, which runs 3.1 through 3.1.1
The chart below shows all fifteen supported Macintosh models, and what versions of A/UX they will run - Green indicates a supported combination. Note that A/UX requires a PMMU (Programmed Memory Management Unit) and an FPU (Floating Point Unit). The PMMU is integrated in all but the original Mac II. The Centris 610/650, and some low-end Quadra 610's shipped with a 68LC040 processor (no FPU). Before installing on one of these models, you will need to replace the LC040 with a full 68040 processor.
| Model / Version | 1.0 | 1.0.1 | 1.1 | 1.1.1 | 2.0 | 2.0.1 | 3.0 | 3.0.1 | 3.0.2 | 3.1 | 3.1.1 | Source |
| Mac II | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes | comp.unix.aux |
| Mac IIx | no | yes | yes | yes | yes | yes | yes | yes | yes | yes | yes | comp.unix.aux |
| Mac IIcx | no | no | yes | yes | yes | yes | yes | yes | yes | yes | yes | comp.unix.aux |
| Mac IIci | no | no | no | yes | yes | yes | yes | yes | yes | yes | yes | comp.unix.aux |
| Mac SE/30 | no | no | no | yes | yes | yes | yes | yes | yes | yes | yes | comp.unix.aux |
| Mac IIfx | no | no | no | no | yes | yes | yes | yes | yes | yes | yes | Doc ID5424 |
| Mac IIsi | no | no | no | no | no | yes | yes | yes | yes | yes | yes | Doc ID6588 |
| Quadra 700 | no | no | no | no | no | no | yes | yes | yes | yes | yes | Doc ID9129 |
| Quadra 900 | no | no | no | no | no | no | yes | yes | yes | yes | yes | Doc ID9129 |
| Quadra 950 | no | no | no | no | no | no | yes | yes | yes | yes | yes | Doc ID9129 |
| Centris 610 | no | no | no | no | no | no | no | yes | yes | yes | yes | Doc ID14662 |
| Centris 650 | no | no | no | no | no | no | no | yes | yes | yes | yes | Doc ID14662 |
| Quadra 610 | no | no | no | no | no | no | no | yes | yes | yes | yes | Doc ID14662 |
| Quadra 650 | no | no | no | no | no | no | no | yes | yes | yes | yes | Doc ID14662 |
| Quadra 800 | no | no | no | no | no | no | no | yes | yes | yes | yes | Doc ID14662 |
Note: While the Mac II, IIx, IIcx, IIci, IIsi, and the SE/30, will run A/UX 3.1.1, performance will be less than spectacular. The "wicked fast" Mac IIfx would probably be okay, but I would recommend a 68040-based Mac for A/UX 3.1.1. The Mac SE/30 will run A/UX 1.1, but it was not officially supported. The IIcx may be able to run A/UX 1.0.1 - I can't find documentation to confirm or deny. If you have the manuals for A/UX 1.X please contact me.
Hard Drive and Memory Requirements:
A complete installation of A/UX 3.0.1 will require about 80MB of hard drive space (160MB recommended), and 8MB of RAM (16MB recommended). Apple Support Doc ID9129 I have a Quadra 610 that runs quite nicely with an 810MB hard drive and 16MB of RAM, and a Quadra 800 that smokes with 2GB and 64MB. Try to keep your specs within reason though:
"When the Apple Workgroup Server 95 starts up, the fsck command is run from the A/UX Startup application. It cannot check a file system larger than 2GB. Therefore, limit the size of your root file system to 2,097,151 KB so that the root file system can be checked at system startup. Once A/UX is running, the fsck command can check file systems as larger than 4 GB." -- A/UX 3.1 Update ReadMe
CD-ROM Drive:
Just because it's got an Apple logo on it doesn't mean it's going to work... A/UX is rather particular about the cd-rom drive. The comp.unix.aux FAQ lists the following drives as 100% compatible: AppleCD SC, CD-150, CD-300, Toshiba XM3201, XM3301B, XM3401, XM3501, DEC RRD42, RRD40 (LMSI CM-212), Sun CDROM (Sony CDU-8012?), CD-Technologies Porta-Drive, Chinon CDA-431, Denon DRD 253. The faq also states that A/UX 3.1 adds support for NEC cd-rom drives... Unfortunately, it doesn't specify which models.
Personally, I've used the AppleCD 300 Plus (Sony CDU561-25), AppleCD 300i Plus (Panasonic/Matsushita CR-503-K), AppleCD 600i (Panasonic/Matsushita CR-504-C), and the Toshiba XM6201B to install A/UX. Others have reported success with the Apple 12X (Panasonic/Matsushita CR-507-C), Pioneer DR-U12X, Pioneer DVD-303S-A, and the Pioneer DR-U16S. I suspect the operating system needs a cd-rom drive with a 512 byte sector size (many newer drives use a sector size of 2048 bytes) or a drive that responds to the "MODE SELECT" command. If you successfully install A/UX using an "unsupported" drive, please email the make/model to me or the maintainer of the new A/UX faq.
Network Card:
The comp.unix.aux FAQ lists the Apple EtherNet card, 3Com EtherLink NB, Asante MacCon, and StarNet cards as compatible. I haven't tried it myself, but I'm told the 10Mb Cabletron Ethernet card works in A/UX 3.0.1 - driver disk Others might work, but your safest option is to choose a Macintosh with onboard ethernet like one of the Quadras. Personally, I have used the MacCon MC3NB under A/UX versions 2.0 and 3.X with success. As with the cd-rom drive, if you get an unsupported network card to work, please let me know!
Video Card:
Unless you're trying to install A/UX 1.X, don't worry too much about the video card. If you're installing A/UX 2.0 or higher on a supported Macintosh, you probably won't have too many issues. However, the older versions are not quite so forgiving. "All video cards that work with A/UX 1.0 or 1.1 must have a special A/UX code resource in them (the one exception to this is that Apple 'toby' card which is hard coded into the kernel)" - comp.unix.aux. The toby framebuffer (Macintosh II video card 820-0198) has its own limitations - It cannot sync to a modern monitor.
