Ignoring the obvious "dmd is truly blazing fast" quip, wildly curious how this happened to you twice? Was it the PSU? Only once heard of a house fire caused by a computer, but no information on component actually caused it.
After that, I set the computer on a metal plate to keep a fire from spreading to the floor.
Some years later, the PSU went out with a bang and a lot of smoke.
(dmd is so fast, the computer doesn't have time to heat up!)