Monitor Upgrade - moving beyond my GPU?

Probably yes, also the Hz of the monitors will impact your experience in gaming if your PC can't match the fps=Hz or > you will feel lag. Might be better to think in a GPU upgrade . You can start to feel your PC slower as well , it happened to me as I used more monitors with a 1060

Personally I wouldn’t upgrade your monitors until you know a GPU upgrade is also in sight. Yes a 1060 can play some games in 1440p, but not a lot of them (speaking as someone who went from 1060–>3080). You’d be spending close to $600 for monitors just to play in low-medium settings when you could be playing in high settings at 1080p. That’s not including whatever Hz you’re looking to get (I’d recommend 1440p 144hz), which the 1060 will certainly struggle with getting consistent 60fps at 1440p in a lot of games. What I did was set aside the money for the monitor until I was ready to upgrade my GPU, then did it all at once. Ended up spending slightly less on a monitor since it had been about a year or 2 since I put the money away.

I had this dilemma recently. I had a 75hz monitor with a gtx 1080. In some games like halo for example I was getting 120+ FPS but was getting terrible screen tearing. I debated for a long time on what should I do. Just use vsync? Nah I wanted them frames. I knew my 1080 would not get me the frames I wanted in 1440p. The thought of me even seeing a 2080 anytime soon doesn’t seem resonable. So I spent $300 on a decent 1080p monitor with 144hz and gsync. I’m happy with it for now but who knows down the road I maybe upset I didn’t get a 1440p monitor and just ran it at 1080p.

Not really for 90% of stuff, maybe for 10%, and there is the always 0.1% pedantic ass to prove a point, but the latter tends to start off: "but with raytracing..."

The 90% of stuff. Is it the 3 or 6GB VRAM version? You might run into some issues if its the 3GB version just due to VRAM issues. A second monitor might need up to about 250MB of VRAM just to run. Depending on what your doing. This is sort of a case of if your hitting your card with enough load for that to be an issue, is more the straw that broke the camel, but you already have a camel size pile of straw on it already.

The 10% stuff, it really depends on what your doing and what you have now. Going from 1080 to 1440 is ~2m to ~3.6m pixels worth of processing to do, or about 60% more load. So as long as your not say running 2 games, 1 on each monitor, as long as you can take that extra 60% load, your not going to notice a difference. Keep in mind the 1660 can do 1440@60 and its a generation newer, so you might have to drop a few of the more demanding settings a notch.

But it really comes down to what your doing and what settings your happy with. For some the idea of playing with less than "All the FSP" is heresy. For me, give me ray tracing at 4k/30 FPS any day. For a GPU, an extra monitor really isn't that big of a load, think the difference between keeping a mental tally of what your spending on groceries before you check out (it's a lot of simple work) vs say differential calculus (gaming loads)

Change the secondary monitor to a lower resolution