I would echo Giles advice on not getting any PS/2 accessories. There were some motherboards that had some keyboard legacy setting in their firmware. I might be completely ignorant on this matter, but I believe the setting was for OSes that didn't have USB drivers.
*** Is it just a superstition that I read
somewhere, that there is there a memory access speed advantage, to
using more DIMMs to get the desired total memory size ?? For example, that a
dual-DIMM 2x8GB configuration provides faster memory access than a single
DIMM 1x16GB ??
Some motherboards would interleave their memory accesses. I don't know if that's true today.