Need a new graphics card

[Bobby7Deals]

Hey, I'm not all that computer-savy and just joined. I was hoping someone here could offer me some advice/explanations? I want to game on my PC with some pretty high settings. I want to run games like Guild Wars 2, Tera, Tomb Raider, Dead Space 3, Crysis 1 and 2 on max settings.

Specs:
AMD FX-6120 3.5GHz
10GB DDR3
1TB HDD
AMD Radeon HD 7450
300 Watt

Dimensions:

Height 16."'
Width 16.2"
Depth 6.9"

Additional Information:
http://www.tigerdirect.com/applicat...mc=Email-_-WebletMain-_-WEBLET03ORDER-_-Deals

Pictures:
http://I.imgur.com/OoR42CH.jpg?1
http://I.imgur.com/vIn9rND.jpg

I'm not really sure whether a graphics card I can buy will fit into the computer. I'm also totally lost with this PCI business, since all the graphics cards on newegg seem to be PCI 3 or something and it doesnt appear that this computer has that, and I'm not sure if that makes a difference. Lastly, from what I've read, my PSU may pose a problem, but I don't know how I'm supposed to find out. If someone could recommend me any graphics cards with a price of 300 (though preferably less), that'd be great. Or if they could just elaborate on any of the questions I posed above. Thanks in advance.

 

[hellokitty[hk]]

HIS IceQ X H785QN1G2M Radeon HD 7850 1GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card

Rosewill CAPSTONE Series CAPSTONE-450 450W Continuous @ 50°C, 80 PLUS GOLD Certified, Single +12V Rail, ATX12V v2.31 / EPS12V v2.92, SLI Ready, CrossFire Ready, Active - PFC Power Supply

The 7850 isn't a huge card but you will want to measure your case just to be sure.
Look up what a PCIx16 slot looks like, find it on your motherboard, and measure the length starting from the back of the case.

 

[Jad Chaar]

HIS IceQ X H785QN1G2M Radeon HD 7850 1GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card

Rosewill CAPSTONE Series CAPSTONE-450 450W Continuous @ 50°C, 80 PLUS GOLD Certified, Single +12V Rail, ATX12V v2.31 / EPS12V v2.92, SLI Ready, CrossFire Ready, Active - PFC Power Supply

The 7850 isn't a huge card but you will want to measure your case just to be sure.
Look up what a PCIx16 slot looks like, find it on your motherboard, and measure the length starting from the back of the case.

I dont think that can run Tomb Raider at max settings (Ultimate Settings). He would need to run High settings (2 away from max) to get 60 FPS.