I am trying to figure whether i should buy a 1070+144hz g sync monitor or buy a 1080ti without monitor. I already have an 80hz freesync monitor. I know freesync wont work but would fast sync help for games like pubg and six siege.
Based on that, you'd be fine with a 1070Ti and a G-Sync monitor. There's no shortage of good quality stuff out there for either item, just be patient and do your research. Unless you're looking to go 1440p+, there's little reason to go all in on a 1080Ti. It's just not worth it in my opinion.
It depends on the resolution you're looking to play at honestly. A 1070 @ 1080p 144Hz is pretty much assured in just about everything but it's not as guaranteed at 1440p. If you wanted that, you're looking at 1080/Ti level cards. Depending on what you are looking at in terms of monitors (TN, IPS, VA) and size or resolution, it may be best for you to wait a bit depending on your budget.
Fast sync should work or so I would think. What GPU do you have now?
What GPU do you have currently? And what monitor do you have currently?
If you've got a 60-75Hz 1080p monitor, a 1080TI is a total was of money.
What kind of budget are you working with? A 1080TI is ~$650 or so.
For that kind of money, you could have a 1070TI (essentially 1080 performance) and a pretty solid monitor
Within budget(ish) either:
1080p Ultrawide 75Hz monitor
1440p 144Hz
Work.
Currently i have an r9 290 and lg29ump68. Im planning on building a new pc with i7 8700k and picking up 1070 with monitor or 1080ti without. Im planning on using it in games like six siege and pubg. I will be playing in 1080p.
A monitor should last for several generations of GPU, so go for the best you can monitor wise and then let the GPU's grow into it, with G-Sync if you are underpowered it doesn't matter much.
Based on that, you'd be fine with a 1070Ti and a G-Sync monitor. There's no shortage of good quality stuff out there for either item, just be patient and do your research. Unless you're looking to go 1440p+, there's little reason to go all in on a 1080Ti. It's just not worth it in my opinion.
Do you think fast sync will help me as much in games like six siege and pubg where fps is 100+
Honestly? It's hard to say but it couldn't hurt. I'd probably be inclined to tell you to use V-sync and lock your frames to your panel's rate until you upgrade to a g-sync panel if you buy a new Nvidia card. Feel it out by trying it with it on and off or frames locked or unlocked. I know you mentioned that tearing or stutter is a major issue for you and that's what you're looking to avoid, but it's going to take some hands on play to find out what works best in the interim.
Good luck. I just bought a 1440p 165Hz G-Sync monitor to go with my 1080 and it's a thing of beauty.