GPU Upgrade

[Ragern]

Hey, recently i made topic about updating my pc and most of people said its kinda not worth to upgrade my gtx 1070 but i still kinda want to do it so i could give my old gpu to a friend as a birthday present. That's my actual build:
Case : Corsair 780t
Gpu : Gtx 1070 asus strix oc
Cpu : Ryzen 5 2600 - stock
Cpu cooler : Arctic freezer esports edition double fan
MOBO : MSI B450 GAMING PRO CARBON AC
Memory : G.Skill DDR4 Aegis 2x8GB 3000Mhz
SSD : ADATA XPG SX8200 Pro M.2 NVME 512GB
PSU : Seasonic focus 650w platinum
Screen : AOC C24G1 24

Ill list some of the options with prices:
Rtx 2070S:
Gigabyte aorus - 686,18$ (new)
MSI gaming x trio - 665,69$ (new)
Zotac amp extreme - 655,69$ (new)

Rx 5700 XT:
Sapphire Nitro+ - 573,48$ (new)
PowerColor Red Devil - 583,73 (new)

Rtx 2080:
Asus rog strix oc - 678,76$ (refurbished with 24 months of warranty)
MSI trio X - 742,79$ (Used with warranty till end of 2022)

Rtx 2080S:
Gigabyte AORUS WF 8G - 819$ (Used with warranty till 21.01 2024 - new one is 960,25$)

As u can see i listed rtx 2070 only new and rest is used only because of small market for used high end products in my country ( Poland) Im kinda thorn between a new 2070S and used 2080 since they kinda close in price range (maybe i can ask for some discount on used ones) but if they aorus is worth ill go for it. I got more or less 2 weeks before my mate got birthday so ill try to update post daily if i find more offers.

PS. Atm i got this aoc screen, how does it work if ill get another screen but with 240 mhz, will that be a problem of any sort? Or if ill get a screen that is 4k for movies or smh will that be a problem to used 1080p and 4k at one computer? Sorry for "newbie" question i just have no idea how it works.

[InstaFire42]

All seem like good GPUs for 1080 240hz, and yes you can use a 4k monitor and a 1080p monitor at the same time. It might hurt your performance a little but nothing too bad. Just make sure the primary display is the 1080 240hz monitor in Windows