$2000 is too overkill IMHO. It's already overkill at $1500. I'm building a friggin' micro computer with a 4GHz quad-core processor (45nm with 12MB L2 Cache), 4GB of RAM, and a 9800GTX overclocked to the point where people would cry from looking at how much I torture the components... and it doesn't cost more than $1200! I mean... top-notch coolings and everything included! For $2000, I can only imagine... of building a computer that can play Crysis on all Very High settings... at 1920 x 1200... with 16x AF... at 25-30FPS!
To get full speed (or over) in PCSX2, you don't need more than $1000 for ONE computer... and then you can use the rest to get yourself a 1920 x 1200 monitor to accommodate that monster.
Edit: Listing of components required for over full speed in PCSX2:
CPU: Intel Core 2 Duo E8400 @ 4.5GHz ($230 - on average)
RAM: 4GB of DDR2 operating at 1066MHz ($200 in total)
MB: DFI Lanparty... something-ish... (either P35 or X38) ($250)
VGA: GeForce 9800GTX ($340)
Case: Something good... ($150)
PSU: Something EXTREMELY good ($130)
Cooling: $200 in total for extreme air, $550 for extreme water
$1600 for air cooling, and $1900 for water cooling
That's overkill right there... and it should be way too enough. Very few games would run less than full speed with such a setup... and you can put your computer inside a volcano... since it won't explode with that amount of cooling.
My own computer is like this:
CPU: Intel Core 2 Quad Q9450 @ 3.80GHz (4.00GHz might be possible... once I do the NB volt mod on the MB) $340 already with overnight shipping and everything... sincerely!
RAM: 4GB of Kingston HyperX 1066MHz DDR2 ($145 already with tax and shipping)
Mainboard: ASUS P5E-VM HDMI ($150 already with tax and shipping) <= vDroop mod credits go to Allsop. But the NB volt mod might go to me... if it DOES work.
VGA: eVGA GeForce 9800GTX ($360 already with shipping and tax)
PSU: PCP&P Silencer 610W ($130 already with shipping and tax)
Case: Antec NSK3480 ($120 already with shipping and tax)
Cooling: $120 in total for top air cooler, top NB cooler, top air VGA cooler... and case fans
Other mumbo jumbos (HDD... etc...) $100
$1465 in total. Delivered all in three days right at my door... and pack some serious punches right there.