PSU - GPU upgrade

jake1234

Honorable
Jan 18, 2014
3
0
10,510
PSU question. I've read dozens of answers on here and have calculated my cpu but I'm still concerned I'm doing something wrong as this is only my second install, very new to this.
I'm upgrading my gpu to an asus gtx 760

My set up at the moment is
AMD FX 6300 3.5ghz - 4.1 turbo
16gb ddr3 ram
500w PSU
Motherboard - gigabyte ga-78lmt-usb3
GPU: radeon hd 7750 vtx 1gb
aerocool 2000 fan controller
I have the galaxy evo case with the 3 standard case LED fans
hooked up to a 42 inch full HD tv with HDMI cable (i don't know if this comes into play)

My question is, I'm pretty sure i need a bigger PSU to run the new GPU - will a 650 cover it? Or do I need a 750 to have the psu running at 70 -80% efficiency? Any help would be greatly appreciated and if i need to give any more specs let me know, thanks everyone.