I referred to drives over 5 years old, which are generally under 10GB incase you can't remember how old yours is. The more slices in a Risc PC, the less air from the fan will pass over the main drive located in the tray at the bottom, so is likely to prove more problematic than a single slice machine.
But don't get complacent, drives can fail at any time no matter how old, so the first thing to do is get a backup strategy in place that is quick and easy to perform, which will allow you to do it more often. The drive in my DVR has just failed completely, it was only 6 months old, and an 80GB Maxtor like in my Iyonix. Typically it happened at the worst possible time - just after getting back from holidays with lots of unwatch programs on it. But luckily I'd backed up all the films that were on there to DVDs just before leaving.