I actually did an mATX retrofit on an old PowerMac G5 tower I picked up on Craigslist for $20. Took some Dremel work, an adapter motherboard tray, a front panel

I actually did an mATX retrofit on an old PowerMac G5 tower I picked up on Craigslist for $20. Took some Dremel work, an adapter motherboard tray, a front panel conversion kit, some Noctua NF-A9 fans, uh, an SFX-L power supply and a few sliced fingers - but I'm very happy with how it turned out! The airflow really can't be beat, it's a gorgeous case, and it's remarkably quiet. There's a subreddit for this, r/G5mods