Best video card for 240 watt psu

I need a video card for a old hp low profile pc that im gonna use as a living room box. The thing has a 240 watt power supply and a 25 watt max power rating on the pci express 16x. I have no idea what version of pci express it has and theres also none of those fancy cable coming out of the power supply that you hook up to the gpu to give it more power, theres no 8 or 6 pin adapter things. so thats all the specs I got so what do you think. im lookin at a price range between $1.00 to $50.00. Also please dont mention that i should just upgrade my power supply, its not a option.

Thanks for any help

 

 

also heres the acual pdf of the manual for this, its the sff version  http://h18000.www1.hp.com/products/quickspecs/13412_na/13412_na.PDF

You might look into a single-slot 6670; great card for low-end low-power systems.

looks pretty good, any brand recommendation?