XP 64? use or not

Building some computers for my friend and it just hit us we might need 64.

specs are intel core2 quad, p5e asus, 8600gt, with 4(1x4) gigs of ram.

these are for rendering with maya mainly and ive never had a need for 64 with my own computers. should i download, i mean buy, 64 or stick with oldschool xp

>>9
Those were my thoughts as well, when I first asked. Still seems to me that 64 bit doesn't offer much of a performance improvement. Another thing is that storage is probably the largest bottleneck these days. There's a reason why Microsoft recommends RAID0 for Vista.

>>10
>The only revamping required _is_ a quick recompile.

Well ok, provided the compiler does its job well. Still, all those enhanced instruction sets of the past, like MMX, SSE etc do require lots of hand optimizations in the code and there are still not many applications that make heavy use of those. And >>7 seemed to suggest that such optimizations would also be needed in the case of 64 bit architecture to make optimal use of the advantages of the architecture.