OK -- I think this was a kernel mismatch. FC5 just came out with kernel 2.6.17-1.2145 and when I first instaleld and updated it was at 2139... 2139 seems to break DOSBox 0.65. Anyway, updating to 2145 seems to have solved the issue.

I've used dosbox on several other systems before without issue but it has been a while since I've installed it on a Linux system, so bare with me if I am missing something obvious... I just installed FC5 on an older PC and then installed dosbox 0.65 with yum (command was "yum install dosbox") but …