Discrete GPU with roughly double power of Intel HD 4600 on i5-4460

[notneps]

If I wanted to add a GPU to an HTPC/light gaming build, what would be a reasonable area to start looking? I don't want to spend too much, as no hardcore gaming is going to be happening, but it can already play decent framerates at the games I play at 1080p, and I don't want to buy a discrete GPU that will give me like 10% extra FPS. I'm looking for at least double performance at minimum.

Would a GTX 750 Ti do it? Or GTX 750?

 

[LucoTF]

Either of those would be a solid upgrade for you