lmao the 530 is a 10 year old machine. You will NOT be able to put ANY CPU, even high end core 2 (They will NOT take Core 2 Quads depending on the motherboard. A 530s for sure will not and for the 530 there was 2 motherboards. One that would take on and one that won't) and honestly even the most powerful C2Q you could put in there won't even come close to what the G5600 can which is like 8 Generations of Intel CPU's later if not more.
Take the 530, Toss it. You can't even use the case. The I/O bracket is built into the case and non removable let alone it will not be able to fix a GPU that would be worthy anyways.
Just build something form scratch. Don't even bother with upgrading anything on that thing lol. Its funny because I have...