Which computer upgrade would be better for me?

I recently put together some things to sell and the money i get from them can either get me a new motherboard with a new processor or a new graphics card. However, i don't know which one would be better to have. I currently have an AMD A6-3650 processor with the gpu cores disabled running a Radeon 7770 GHz edition instead. I can upgrade the processor to an i3-4150 along with getting a new motherboard to fit the socket, or i can upgrade my graphics card to something like a Nvidia 750 ti. I don't know which one would be more beneficial for me. I play some league of legends along with minecraft every once in a while, other than that i browse reddit or something.

and also, if i wanted to steam, which one would be better.

Personally I would go with the i3 4150 and this will significantly improve your gaming performance especially when combined with the HD7770 ghz edition…
I noticed this when moving from the basic Pentium G620 to a core i5 3330… This was a massive upgrade and even though I kept my radeon HD6790 I noticed a massive improvement in the cards performance due to the i5 3330… My previous G620 was obviously bottlenecking my HD6790 and I was only getting around 75%( if that ) of the HD6790, s maximum performance
that said for around £30 more you could go with the "Intel Core i5-4430 3.00GHz (Haswell) Socket LGA1150 Processor "( http://www.aria.co.uk/SuperSpecials/Other+products/Intel+Core+i5-4430+3.00GHz+%28Haswell%29+Socket+LGA1150+Processor+-+Retail+?productId=55831 ) which would improve on the i3 4150 and by quite a margin
in regards to the AMD A6-3650 its ok but i've never rated apu, s that much… Intel processors have much better performance and you only need to check their passmark scores to see that.
although the GTX750ti is a amazing card I wouldn't recommend it to use with the AMD A6-3650, however the i3 4150 or the i5 4430 and your talking
go with the i3 4150, and if your budget can stretch to it the core i5 4430 would be a outstanding upgrade that would totally transform your rig
I hope this helps kyle… Any questions let me know