Most powerful Graphics Card that DOES NOT require external power?

Hi, I sold my old gaming PC due to some issue blah blah blah, and I'm saving my money for a new one.

I'm 14, not poor but DEFINETELY not rich, so I realised I'm not getting a PC anytime soon.

I currently play a lot of source games and minecraft on my fathers office PC, which has an i3, 4gb ram etc.

I wanted to get a good graphics card and put it in, but the power supply would not support that much power, and I can't change the power supply as it is not my PC.

Anyway, what is the best (most powerful) graphics card that will run off of the PCI-E port only?

Guest

Oh yes, and (I think) I have a 300 watt power supply, if that helps.

Curtis

Well, I know that there's a model of the Geforce GTX 750 Ti that doesn't require an additional power connector, and that can play most modern games (besides next-generation) on highest settings, resolution, usually maxing at 60fps.

Also should be noted that it could still run perfectly on a 300 watt power supply.

http://www.amazon.com/...B00IDG3IDO

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