Are these video cards compatible with my PC?

I want to upgrade the video card for my Dell Dimension E521:

http://www.dell.com/us/en/dfh/desktops/d…



It has expansion slots

PCI: 2 Slots

PCIe x1: 1 Slot

PCIe x16 (Graphics): 1 Slots



And a 305 Watt DC power supply.



Here are the video cards:



XFX Radeon HD 5570 650MHZ 1GB 1.0GHZ DDR2 HDMI DVI VGA PCI-E Video Card:

http://ncix.com/products/index.php?sku=5…



Powercolor Radeon HD 5570 650MHZ 512MB 1.6GHZ DDR3 DVI HDMI VGA PCI-E DIRECTX11 Video Card:

http://ncix.com/products/?sku=52258&vpn=…



Which one is compatible with my PC? If they both are, which one would give me the highest graphic quality? (I would like to be able to play Starcraft II smoothly)

Thanks in advance!|||http://ncix.com/products/index.php?sku=4…



this one would be waaay better, but whichever you pick, they all seem to require a min of 400w power supply so keep that in mind otherwise the card will run hot and slow and may burn up.|||Will you be able to play starcraft 2 smoothly?



No



Are these cards compatible with my pc?



Probably. You're power supply is twice as small as it should be|||Suggested ATI Radeon™ HD 5570 and 5550 512MB DDR3 System Requirements

400 Watt or greater power supply recommended