It may become possible to tweak X-Plane to maintain 45 FPS within a few months, however as long as there's no way to actually LOCK it to 45 FPS, it won't be very useful. But it's certainly possible to suggest this as a desired feature to Ben.

I'm a newbie to the flight sim scene, but have years of experience with car racing simulators, where the sim cockpits and hardware are actually quite similar.

I have two triple monitor setups; one with 3 * 27" Dell Monitors @ 60Mhz (5760 * 1080) and a second with 3 * Acer Predator Z35 (G-Sync enabled) @ 200Mhz (7680 * 1080). 

In X Plane 11, my i7-8700K / GTX 1080Ti with 16Gb RAM potters along at around 60fps using the default graphical settings that come out of the X Plane 11 box @ 7680 * 1080.   

I like high frame rates for car racing, and target 90FPS or higher.  Below 90 FPS and I can feel the screens juddering.  Between say 90-120FPS I can see a marginal improvement in game smoothness, but nothing to pay a lot of extra money for.  Above 120FPS I cannot see a difference.  As a result I run my Predator Z35 monitors at 120Mhz to reduce PC stress. 

But another side benefit of higher refresh rates is eye fatigue.  My eyes would get sore and dry after about 20 mins on the 60Mhz monitors, but I can game for over 4 hours on the Predator Z35s before I start getting eye fatigue.

Now as I am new to flight simulators, my advice may not be relevant as Flight Sims may be able to run fine at much lower framerates than car racing, but this makes G-Sync / Freesync much more important.  In my experience (once again for Car Racing), I cannot see any Nvidia G-Sync benefits when running medium to high frame rates (say 60FPS or higher).  However G-Sync really comes into its own when the PC is struggling with low frames.  Say at 20 to 40fps G-Sync really smooths out the game.  Below say 20fps, nothing seems to save the game from jerkiness.

For car racing my monitor priority would be refresh rate (no less than 100Mhz), followed by screen size, resolution, and Nvidia G-Sync or FreeSync.  Don't pay extra for triple curved monitors as while they work fine, I don't perceive any benefit over flat monitors.

If the budget is limited and you cannot get a PC that can play your games at a minimum 60+ fps, then G-Sync / Freesync becomes the highest priority as it will smooth gaming below 60fps.

I don’t like to use my other Triple Dell 60Mhz gaming setup as the experience is quite jarring in a bad way compared to the Acer Predators.  I also don't like car racing on TV's.  The input lag is also jarring vs gaming monitors.

My summary is to get G-Sync / Freesync with a minimum 100Mhz Refresh Rate, and then the largest screen(s) you can afford.

 

Cockpit #1 - Acer Predator Z-35 (7680 * 1080) @ 200Mhz

Cockpit #2 - Dell 27" (5760 * 1080) @ 60Mhz

On 11/26/2017 at 11:29 AM, Beef36 said:

However G-Sync really comes into its own when the PC is struggling with low frames.

Hi Beef36,

Thanks for the feedback. You got some impressive setups there. 

With G-sync ON, can you really feel the difference in XP11 when fps go below 60 to let's say 40-45 region?

Is there noticeable screen tearing in XP11 on a 144 Hz monitor without G-sync / Freesync?

Cheers