Benchmark 32bit vs 64bit

[Gert]

Actually, in 64 bit mode the processor exposes more registers (general purpose and SSE), therefore the compiler can optimize better by keeping more temporal variables in registers. Hence, tasks that are executed mostly on the CPU may gain from running native 64bit as this article shows:
http://www.phoronix.com/scan.php?page=ar..._pae&num=1

However, the first benchmark in above article also shows that for computer games (that offload a lot of the work to the GPU), the choice of 64 bit over 32-bit doesn't play a big role and a difference may not be seen at all.