like the list's advice on what sort of mainboard is best to pair this with; or, rather, what sort of mainboard I definitely shouldn't pair it with. I'm running Ubuntu, and I know its hardware support is pretty good, but any advice you can offer would be appreciated.
The biggest issue with linux compatability is usually with the onboard peripherals, such as audio, network, IDE/SATA controllers. If you're going for an Athlon 2400, you can look at older revision motherboards, so save a lot of the hassle you might find if you were getting the newest Nforce4 board. If you're getting SATA, check the status of SATA support for the controller (http://linux.yyz.us/sata/). If you're wanting to do SATA RAID especially, check that page out - a lot of the SATA RAID controllers embedded on motherboards are fakeraid only, and so only work with binary drivers (or not at all in Linux). They'll almost all still work as basic SATA controllers though. I've used gigabyte boards in the past, and currently have a soltek board I'm quite happy with. Gigabyte boards used to have a tendency to blow capacitors, but the 2 year warranty means you've got a good chance of getting it fixed anyway :)