I am curious though, although the spec we typically used (e.g. dual AMD Opteron 2.6GHz, 8 or 16GB RAM) was good - it was not so far of the 'headline' (shop window) specs of many a desktop machine that I have used. For example, I am now using a commodity machine which has 4G RAM, Dual Core Intel 2.8Hz, and cost ~ $400.
However - the DL was clearly much much faster. My reference is compiling a similar code base which on the DL might take a couple of seconds, and on the commodity hardware 10 seconds (assume the machines were doing nothing else, so minimal load factor & ram usage).
So my question is, given similar headline specs (RAM & CPU), what is it about the DL's build and architecture that makes it so much faster than a commodity machine.
Update: the question might be better phrased simply as
"given a set CPU and RAM, what are the other server architecture & component features that significantly influence it's performance?".