That (black end) plugs into the end of your video card and the other two plug into any free power connectors on your power supply.
This cable isn't needed if your power supply already has a built in video card connector.
I can't see what the rating is on your power supply from the pictures, but you will also want to make sure it can provide enough power to your video card.
Looks like you have two SATA power connectors free. You would attach an adapter to each of these (giving you two molex connectors). Then use the molex to PCI-E cable that came with your card.
However, as others have said, I don't think 300 W will cut it.
You will need to replace your PSU with a more powerful one that has the required connector. Although you can get by with only 450W, in your place I'd probably choose at least 500W, and definitely a quality brand. This list is dated, but will give you a place to start: http://www.tomswiki.com/page/Tiere [...] gs?t=anon. Choose one from tier-3 or better.
------------------------------There is ALWAYS a drone. Exactly where, or how many drones you will encounter may vary, but that there will be at least one will not.
Reply to jtt283
See the black plug thats plugged into your dvd rom drive..... ?......... those are the kinds of plugs that plug into it. Try and find 2..... I see 1 just hanging there. there may be one hidden. You may get away with using just 1 I don't know.
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