I'm looking to build a machine for some fairly hefty audio, video and graphics processing. I'm having trouble getting through the information about x86-64 processors and motherboards and chipsets. Sound and graphics cards, hard drives and optical media I can deal with. Basically, I'd like to aim for a dual processor machine with plenty of memory. Unfortunately, I can't afford to lay out for the final spec in one go so I figure I'll start off with lower spec and upgrade as I need to/can afford to. To that end, I have some questions:
Which processors can I use in an SMP setup? I know they need to be a "pair", but do all the x86-64 units play SMP, or only a few?
Is it possible to upgrade from an Athlon to an Opteron on X2?
Any reccomendations as to motherboards would be most welcome.