Improve Build Time on dual processor machine

The i5 is almost certainly a much faster cpu than your Xeon.

I'd guess the Xeon is core2 technology, so the i5 is a later version of the same family and will perform slightly better (instructions per clock).

Until the OS starts swapping, the very large memory makes little difference. The larger cache helps - but only while the code/data fits in the cache. Once some data item exceeds the cache size random accesses (like sequential ones) will be almost always cache misses!