I'm not at all an expert on AMD CPUs honestly, don't take my word for guaranteed certainty. I would definitely recommend piling money up to do one big internal upgrade actually more than anything. Assuming your case, power supply, and etc. are all fine, it'd be highly beneficial to simply upgrade mobo, RAM, CPU, and GPU all in one. Even if it's not the greatest parts available, new or older generations (e.g. Intel Haswell CPUs, GTX900 GPUs vs. the pricier latest), it'll do a world of good.