gulighs1 :
Im very sorry for the Double Post and straying slightly of topic, but this is the very last thing i need you to observe.
My son has almost the same box
Intel Core i7 920 (currently at 3.4 ghz .... working on Event Viewer errors b4 getting into serious OC)
Dell U2410 (didn't want a TN panel as he into photography)
Asus Rampage II Extreme
(1) Seagate 7200.12 in box, 4 in an NAS
Plextor 320AS Blu-Ray Reader and DVDRW Drive
Mushkin Redline 6GB (3x2GB) DDR3 1600MHz w. 6-7-6-18 timings
Antec Twelve Hundred Case
Logitech G9 Laser Gaming Mouse
Prolimatech Shadow w/ twin Enermax PWM fans
Windows 7 Ultimate 64 bit
EVGA GeForce GTX 295 FTW Edition SLI 1792MB
Antec SG-850 SLI Compliant Power Supply (Slightly edged Corsair HX by being quieter)
Logitech G19 Gaming Keyboard (LCD slideshow drivers not Win7 64 bit compatible)
ACM Smart Card Reader
Asus OC Station and Multi Fan Controller
My son doesn't keep GFX cards more than 2 years so DX11 compatibility was a nonissue. Given the fact that he wants PhysX, the 295 is also a cheaper option than a 5870 + a dedicated PhysX card.
If you want the fastest card, can't wait till fermi or the 5870x 2 shows up and aren't doing to keep the card more than 2 years, the 295 remains a viable option:
http://www.tomshardware.com/reviews/best-graphics-card,2464-7.html
"Despite ATI's new Radeon HD 5800-series, Nvidia's GeForce GTX 295 (with SLI-on-a-board) is the most powerful single graphics card on the planet. Essentially two conjoined GeForce GTX 275s, the GeForce GTX 295 offers very notable gains over the Radeon HD 5870 in the great majority of game titles"
Given your budget, a SSD should be considered .... my son opted out cause we both figure that SSD's will get some issues ironed out, increase in size and drop in price by Spring.