Build Advice Upgrade advice

[Chalken]

My current rig:

i3-3240
GTX 660
2x4GB DDR3
B75M MOBO
500w PSU

Which option would be better in terms of performance and longevity?

1. i7-2600 + RX 580 8GB.
2. i7-3770 + RX 580 4GB

I game @ 1080p. I know that this is an old platform, but replacing mobo, ram and cpu would be too expensive for me at the moment.

 

[R_1]

I would get the one with the better GPU. system 1.
when you can afford to replace the trinity (CPU, MOBO, and RAM) that GPU will still be relevant.
the 4GB model will not be useful as long as the 8GB model.

 

[Chalken]

I would get the one with the better GPU. system 1.
when you can afford to replace the trinity (CPU, MOBO, and RAM) that GPU will still be relevant.
the 4GB model will not be useful as long as the 8GB model.

Alright, thank you.