yes, i think i got wrong describing the problem, first the cpu will be upgrade with the motherboard too since nehalem and haswell have different slot, and my target gpu is 1050 ti at max because of the budget. my point to upgrade is how to stick to DDR 3 as long as it possible. I'm not really expecting to get any of RTX even the cheapest one because its for personal use and i don't need them (yet), maybe i'll get the RTX but not in this short time
i'm so sorry for this
I think I might get it. it’s not about getting into the envelope of modern games but staying out of it for cost reasons. Currently haswell still works for modern games and likely will until the consoles are released. The chips that are currently too slow to play modern games are the non k 4/4 chips, which explains the i5 4570. It would be vastly less expensive right now. Likewise the non z boards that would fit it. The problem with this plan currently is only the high end of the 30xx GPUs have been so much as announced, and AMD’s response is not even out of wraps.
Because of this low end GPUs have not yet reached the obsolescence point you need for your plan to work. A 4570 can easily handle a rx580 or even more, and those are still non obsolete GPUs. I would say to balance a 4570 a 1070 wouldn’t be unreasonable. It’s going to be a bit before such things really get cheap though.