... Of course you had better use a journaling file system with such a setup. My stripped down Windows 7 setup with NTFS will be mining again just two minutes and a few seconds after the original failure.
As for a serial port - if your mainboard doesn't have a built in serial port or a serial pin header (some still do even today) you can get an USB to serial dongle. Check that it uses a chip that's supported on Linux - most should work these days. Then just point your software at /dev/ttyUSB0 or whatever it's called.
Good call on the header on the MB, Im going to use that and see what I can come up with. I tried looking on ebay, but seems like the items are expensive now, so I will have to wait.
Also how do I know if Im using a journaling file system? Im running coinlinux (debian from a USB stick). Im guessing a journaling file system is more tolerant of random restarts?