Qazzy03:
If you only have motherboard slot power I think the best GPU you might be able to get in terms of grunt are these 1650 GTX
For RAM i am assuming you are rocking DDR3?
If so, some cheap deals here $15 for 8GB, https://www.cheapies.nz/node/45586
Yeah, just single slot, motherboard power. Also, PSU only 280W. So I think if I am going to keep this a little bit longer, then the GPU will want to be cheapest around. That's why I thought maybe the GT 1030 for around $150. Note, that's still an improvement on the existing HD 8570. As I say though, that might just be throwing good money after bad, considering the rest of the machine.