How good of a deal can you get on a 580?
A 570 is faster than a 1050 (non ti), but 140 euros better than what you have? Plus shipping and whatever additional costs? ( tax? I don't know for your area)
So if you could go 580 8 GB for at or under 200 euros, ( 50% increase), it would crush your current card.
https://www.youtube.com/watch?v=vzx-us9g86U
Hardware Unboxed 27 game benchmark 570 vs 1060 3 GB.
Should help with your decision.
Also. do you "need" a new card right now?
We do not know what we will see anounced at the CES AMD keynote tomorrow.
If rumours are anywhere close to true, you "may" be able to get Vega 56/ 1070 performance for around the price and power of a 580 by summertime.
Maybe. So I'd wait about a week before hitting the buy button, no matter what you do.