Well, hopefully they'll release a 64 bit version of Bryce  (Maybe hear more at Siggraph? Can Bryce use multicore CPUs at the moment? Couple of things in Bryce I miss using: random skies and clipping terrains acting as a mask)
Anyway,  my suggested spec for perfect PC at the moment is:

-Antec 900 Gamer case. lots of room, very cool (tons of huge fans)

-Hiper 600+ watt PSU (very quiet and has long lead to motherboard needed for Antec case, which has PSU at the bottom)

-ASUS P5K-E motherboard (I went with Gamer Extreme and lot of folk have had huge problems with it, been fine for me thankfully so far)

-8 gig RAM, 64 bit apps and lots of RAM = can throw EVERYTHING you want into a scene, basically. oh I luuuuuuuvs it, it's my preciouuuussss! :p

-Minimum of 2x500 gig Hard drives. 1 for operating system (can also copy data to it for back up) and other for data, in case of crashes. Or 3+ drives, one RAID mirror of operating system drive.
(In future be great to keep OS drive as a flash memory drive.)

-Intel quad core (much better than AMD at moment), 6600 is nice and cheap but, price drop for next up version soon.

-Nvidia 8600 GT vid card with 512 RAM (to carry lots of textures). 8800s are still too expensive IMHO.

I love my new rig, makes things so much sweeter, and Vista is BETTER than XP, when tweaked.

New rig renders x10 faster with Vue and Maxwell than previous P4 3GHz Intel, 2 gig ram, 7600GTS vid card, XP Home (have XP Pro on my dual core game/render alternate).
One scene brought my old system to it's knees, 2% resources left, on new one, 75% resources left! Yummy.

:)

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