15 months ago
Since id be running 4k I probably wouldn't be to likely to break above 60hz or more with a gtx 1080 so is the g sync worth it ?
Think of it like this: You will have the monitor longer than your video card more than likely, are you willing to pay the difference for G-sync? Would you get rid of this 4k monitor if 8k comes out? If the answer is probably not, then just get g-sync.
8k monitors already exist
The issue with monitor advances is hardware keeping up
4K 144hz hasn’t even truly happened
Anything above that is ways away
The point of G-sync is for when your pc can't keep up with the monitor... So with what you've said about the gtx 1080 probably not likely to get above 60fps then your case is exactly why you'd want G-sync.
A 1080 will struggle at 4K in a lot of games
So yes, get gsync
I play at 4K with a GTX 1080 at times and I can say that for less demanding titles like CS:GO, Path of Exile, Diablo 3, Minecraft and such, capping the game at 60fps+ shouldnt be a problem.
However, for more demanding titles such as Battlefield V, Rise of the Tomb Raider & The Division, you likely wont cap the game at 60fps at all times. I played those games with a mix of medium/high (requires manual tweaking) and I usually ended up in the 40-50fps range instead. I had no visible stutters and didnt feel like not having G-Sync was an issue at all.
That being said, if you can get G-Sync, no reason not to but I wouldnt spend $200-$300 more for it.
Do note you can test it yourself by having the card run at a higher resolution and then down-scaling the result. Its not the same but it gets pretty close.