A few days ago I was getting some upgrade parts
for my desktop
and was talking with one of our local PC repair folks that do a number of repairs
for PCs on boats. He said they get 3 or 4 a month, so I figure that's a pretty fair sample.
He said that the biggest problem they've seen for marine
PCs is inadequate ventilation leading to over-heating. He said that people tend to stick them in out of the way, tight places with closed panels
and sometimes even stuff things around them. PC gets too hot and things break. So, it sounds like the best fix for that one is education about location.
I asked him about corrosion
and he said that he's never seen significant corrosion
even on the PCs used in boats. That the machine seems to build up enough internal heat to keep things dry. Of course, he cautioned that unless they are specially built for it, they should not be kept out in the cockpit!
In terms of power efficiency, he has been recommending that people buy regular components, using the current
BTX motherboards for their improved circulation, be careful about buying
efficient components and then underclock the processor. AMD's Cool & Quiet technology also gives the ability to let the PC choke itself down when less is needed and than ramp
it back up when more is needed.
There's also this little calculator which can give some ideas about power consumption
given a system configuration. I've used it several times with good success.