Power Supplies

So, I'm having a hell of a week. My goal is to be able to play Starcraft 2 on the highest settings. To do this, I purchased a new graphics card. Then I realized I don't have the correct cables to hook it up to my power supply, so I ordered some adapters. Then I realized my power supply isn't strong enough to support this graphics card.

tl;dr version: I have a shitty power supply. Can I buy a new power supply with no worries or are certain power supplies not compatible with certain computers/parts of a computer?

10723113416AM[url=http://ms4mesos.net/]Maplestory[/url] | [url=http://ms4mesos.net/]Maple Story Mesos[/url] | [url=http://ms4mesos.net/]MapleStory Mesos[/url] | [url=http://ms4mesos.net/]Maple Story Meso[/url] |

what you need is a psu that is pci-e ready, something like this: http://www.compusa.com/applications/SearchTools/item-details.asp?EdpNo=3973822&CatId=2534