I have an old 166 Mhz computer that is still very viable. The HDD crashed, and I want to replace just that. Does it really matter if I get 5600 rpm vs 7200 rpm? It's only a $30 diff, but that's still $30...
It may be a $30 difference, but 7200 RPM hard drives do have a noticeable performance improvement over 5400 RPM hard drives. However, on a system that old, it's hard to say if it would make very much of a difference.
I would say if you plan on using the P166 for a good while longer, get the 5400 and save yourself $30, but if there is any slight possibility of upgrading in the near future, definitely get the 7200 rpm.
<i>I don't know anything about computers... but I did stay at a Holiday Inn last night...</i>