I used to be a hardcore AMD fan but current core2duo/quadcore is superior to AMD equivalents, and i7 blows them all away.

I doubt anyone else is going to go beyond 10 boxing (doesnt make much sense in WOTLK really) but if anyone else is, the best bang/buck setup atm is 2-4 PCs, each a quad core (q9550 or q6600 OCd, deps on your budget) and each running 3 copies of WoW -- in a month or so the nvidia 260+s or 280s are going to drop to CRAZY prices as the new cards come out too. imo a AMD setup like Sam's is not going to be fun when running more than 1 wow in Wintergrasp/Dalaran, but it doesn't really matter since by the time he gets there it will be deserted and fast FPS.

In 6-8 months the i7's are going to reach $$ levels where they will be the new multiboxers platform of choice, but right now the motherboards and DDR3 memory are x2-x3 pricier than quadcore alternatives, for just a 30-50% performance boost. if money is no object then of course the top of the line i7 + 24GB of memory + Vista64 + the new upcoming quadSLI Nvidia card + Intel SSD will run 5-10 WoWs at 60fps with full graphics cranked on.

I kind of view Sam as the George Costanza of MMOs, you pretty much wanna do the exact opposite of anything he does. Kind of makes me feel bad that he is using a pally tank and shamans though, it probably means ele shamans will not receive too much love beyond patch 3.08

Oh, two problems you are going to run into when 5 boxing 5 instances: (1) SFK is designed for level 13-21, beyond that the XP/hour is not great. Past level 25 its horrible, I think at 27 or so you will get 0 xp. Same issues with SM, you can zone in at 25, past 37 the XP is not that great. But 5 con-level characters will wipe a lot. (2) Most of the instances have runner mobs, it will screw up 5-5ing when each instance has mobs running in different ways and possibly aggroing new packs if not handled asap. I'm not concerned though, you killed the first trash pack in SFK after a lot of wipes so therefore you must have mastered it already.