Ah, well no OS definitely helps.
You were pretty good on your initial list.
The big thing I would change would be I5-2500k rather than I7. Games simply aren't written to take advantage of the extra cores on the I7, so you're spending a lot for not very much return. That's ~$100 savings.
I would also look to step down from 1TB drive to a 500GB drive to save money and noise. But if you do go w/ the 1TB then look at the Samsung Spinpoint F3. Slightly better performance than the WD Caviar Black in several tests, but at a lower price.
The RAM is good, you can pay half again as much to go from CAS9 to CAS7... probably not worth it.
Good call on the video card, that looks to be the value leader atm, especially if you factor heat into the calculation.
Also like your choice of power supply.
I put that stuff together w/ some links to NewEgg.com... before I realized you were a
GWN shopper. You'll want to compare against newegg.ca before you trust some of these prices and promo codes.
CPU + Cooler
Intel Core i5-2500K Sandy Bridge 3.3GHz (3.7GHz Turbo Boost) LGA 1155 95W Quad-Core Desktop Processor BX80623I52500K
**plus**
COOLER MASTER Hyper 212 Plus RR-B10-212P-G1 "Heatpipe Direct Contact" Long Life Sleeve 120mm CPU Cooler
$251 http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.618217&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-RSSDailyDeals-_-na-_-na&AID=10521304&PID=3463938&SID=
(I chose a combo w/ cooler b/c you selected 'K' series chip. So I assume you want to overclock. If you're not overclocking skip the cooler, get regular 2500 -non 'k' chip for $210)
Motherboard
MSI P67A-GD65 (B3) LGA 1155 Intel P67 SATA 6Gb/s USB 3.0 ATX Intel Motherboard (this one is sold out atm, but it's the most likely candidate out of the ones listed on newegg)
$180
http://www.newegg.com/Product/Product.aspx?Item=N82E16813130574
RAM
G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9D-8GBRL
$100
*Alternate RAM
G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Dual Channel Kit Desktop Memory Model F3-12800CL9D-4GBNQ
$48 http://www.newegg.com/Product/Product.aspx?Item=N82E16820231193
Hard Drive
SAMSUNG Spinpoint F3 HD502HJ 500GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
$50
http://www.newegg.com/Product/Product.aspx?Item=N82E16822152181
(Making compromise on size here. 500GB is still plenty of space, but it's cheaper, quieter, and slightly faster than 1TB drive. Easy to add another drive later if storage becomes an issue)
Video Card
MSI N560GTX-TI Twin Frozr II/OC GeForce GTX 560 Ti (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card
$250
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127565
Case
NZXT HUSH White SECC Steel/ Aluminum/ Plastic ATX Mid Tower Computer Case
$85 (w/ Promo code 'EMCKGKG27')
http://www.newegg.com/Product/Product.aspx?Item=N82E16811146053&Tpk=NZXT%20Hush
*Alternate Case
Antec Three Hundred Black Steel ATX Mid Tower Computer Case
$60 http://www.newegg.com/Product/Product.aspx?Item=N82E16811129042
Power Supply
Antec TruePower New TP-650 650W Continuous Power ATX12V V2.3 / EPS12V V2.91 SLI Certified CrossFire Ready 80 PLUS BRONZE Certified Active PFC "compatible with Core i7/Core i5" Power Supply
$80
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371021
OS
Not required
Optical Drive
ASUS Black 24X DVD+R 8X DVD+RW 12X DVD+R DL 24X DVD-R 6X DVD-RW 12X DVD-RAM 16X DVD-ROM 48X CD-R 32X CD-RW 48X CD-ROM 2MB Cache SATA 24X DVD Burner - Bulk - OEM
$19 http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-RSSDailyDeals-_-na-_-na&AID=10521304&PID=3463938&SID=
Total $996...
Alternate build w/ 4GB RAM and diff't case $919