Need help making sure my first build is ok.

Hey all, my name is Mike. I'm new to this site, even though i have been reading these forums for a while trying to learn. So after the announcement of the PS4 i started reading alot of articles about it's performance compared to a nice gaming PC and how it really isn't that powerful compared to one. That got me thinking about building my own gaming pc. So i decided to do some research and read alot on these forums about a gaming pc, and came to the conclusion it's cheaper to build one myself. Plus i get to learn more in the process. I like the idea of being able to know how to fix my computer myself. It's also going to be a great feeling knowing i built it myself. I'm going to be purchasing all my parts from newegg since i like their prices as well. Anyway so i came up with this build and i wanted to know get advice and opinions on my choices of hardware and if there are any tips or advice about changing anything. Here it is. Oh and by the way my budget for this is $1200.00 But if i could keep it a little under it would be great.

Case: NZXT Phantom PHAN-001BK Black Steel / Plastic Enthusiast ATX Full Tower Computer Case - $119.00

CPU: Intel Core i5-3570K Ivy Bridge 3.4GHz (3.8GHz Turbo) LGA 1155 77W Quad-Core Desktop Processor - $209.00

Motherboard: ASRock Z77 Pro3 LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard - $94.99

CPU Cooler: COOLER MASTER Hyper 212 EVO RR-212E-20PK-R2 - $32.99

Memory: G.SKILL Sniper Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1866 (PC3 14900) Desktop Memory Model F3-14900CL9D-8GBSR - $66.99

Hard drive: Seagate Barracuda ST1000DM003 1TB 7200 RPM SATA 6.0Gb/s 3.5" Internal Hard Drive -Bare Drive - $74.99

Power Supply: XFX Core Edition PRO550W (P1-550S-XXB9) 550W ATX12V 2.2 & ESP12V 2.91 SLI Ready CrossFire Ready 80 PLUS BRONZE Certified Active PFC Power Supply - $69.99

Optical Drive: LITE-ON DVD Burner - Bulk Black SATA Model iHAS124-04 - OEM - $17.99

Video Card: SAPPHIRE 100352-2L Radeon HD 7950 3GB 384-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card - $289.00

Operating System: Microsoft Windows 7 Home Premium SP1 64-bit - OEM - $99.00

Total - $1077.90

I was hoping i could get some help and maybe hear some opinions if there are some changes i should make. I'm not sure if the power supply is enough for the video card, and is that a great video card to start out with for bang for my buck? And i plan to overclock my cpu and gpu as well. This is my first post so any help would be greatly appreciated. I just want to have the best system i can have for the money i am going to be spending. Thanks guys.