G-sync display and 30% framerate difference each time I start P3D V4.4

[Gaplus]

First of all, I’ve been using a G-sync display and GTX 2080 in G-sync mode. Each time I launch P3D, there is a difference of framerate about 30%, although I use exactly same startup situation.

For example, a certain situation file, framerate at beginning of the session is about 110 fps with little or no stutter, but next time I start P3D, it was about 80 fps with increased stutters. So, there is about 30% difference between them. Interestingly it has never dropped below 30%. It’s like 110 fps or 80 fps, always experience same 30% drop in other situations too.

Also, this framerate drop happens when I access menu items and manipulate setting during session. Especially, when I change the airport, display option setting, and flight analysis. Once dropped framerate about 30%, it wouldn’t return best performance until restarting P3D. So, in order to get best performance after changing airport, I have to save the situation, close P3D then relaunch P3D. Sometimes just restarting P3D doesn’t solve the problem and I have to restart PC. I think about 4 out of 10 lunches of P3D aren’t full performance.

Incidentally, I had same problem when I’d used 1080Ti and P3D version 4.3. I would really appreciate if I receive suggestions to get stabilized good performance.

Thank you,


(My system)
Intel 7700K
Mother bored: ASUS Strix 270F Gaming
8GB GDDR4 Memory *2.
500GB SSD (Main), 2TB SSHD (Data)

Windows 10 Built 1809

Monitor: Asus PG279Q G-sync monitor (144Mhz)
Video Card: Gygabyte RTX2080

(Peripherals)
Saitek Radio Control *2
Saitek Flight Switch Panel
Saitek Throttle quadrant *2
Saitek Cessna trim
Saitek Cessna Radder


(P3D display setting)
Framerate: Unlimited
No V-sync

[elgreco111]

Maybe try VSync on, Triple buffering on, Frame limit 30 or 42. Do you have HP on or of on CPU ? Can help sometimes to turn off HP.

[AnkH]

Which driver do you use? If I am not entirely wrong, G-Sync is still somehow buggy with applications that do not run in true full screen. Personally, I simply deactivated G-Sync for P3D, as my aim is to have 30FPS in almost all situations and G-Sync on my Dell S2716DG only works from 30FPS upwards.

If you still want to have G-Sync, I suggest a limit of 72 (half of your 144Hz monitor refresh rate) and see if you do not get more consistent FPS like that.

Although G-Sync was designed exactly for alleviating the stuttering when FPS are not constant, the simulator per se is not. You get the best results in P3D if you somehow manage to have as constant FPS as possible and if you get to this point, G-Sync basically becomes obsolete.

BTW: I think the greek guy is talking about hyper threading (HT), not "HP" (whatever HP should mean). And don't ask me why he thinks that 42FPS is a relevant FPS number for a 144Hz monitor...

[elgreco111]

Sorry my fault should be HT, 42 Frames is because I got a programm called FSPS - FFTF DYNAMIC P3D4 at SimMarket.
https://secure.simmarket.com/fsps-fftf- ... p3d4.phtml. This setting is best for me.

[AnkH]

Ok... but still, those 42FPS is simply what suits you best, has no relevance for the topic starter. I use the FFTF Dynamic tool as well, for flying in or out very heavy scenarios (EGLL, EDDF etc.) it is a really nice tool, I agree.

[Gaplus]

Maybe try VSync on, Triple buffering on, Frame limit 30 or 42. Do you have HP on or of on CPU ? Can help sometimes to turn off HP.

Thank you for tips. I tried HT off and found issues are relieved significantly even though there was still little FPS drop. But at the same time, I noticed OS's loading time increase, so I turn it on and add affinitymask=250 entry in CFG, which I found it from other discussions about HT. I guess Windows or BIOS uses HT to enhance disk operation. So far, P3D perform well and no longer required starting-closing it until getting best performance. I kind a feeling there are still issues between HT and P3D 4.4. I thought affinitymask entry was old time technic and wasn't necessary for the latest P3D.

[Gaplus]

Which driver do you use? If I am not entirely wrong, G-Sync is still somehow buggy with applications that do not run in true full screen. Personally, I simply deactivated G-Sync for P3D, as my aim is to have 30FPS in almost all situations and G-Sync on my Dell S2716DG only works from 30FPS upwards.

If you still want to have G-Sync, I suggest a limit of 72 (half of your 144Hz monitor refresh rate) and see if you do not get more consistent FPS like that.

Although G-Sync was designed exactly for alleviating the stuttering when FPS are not constant, the simulator per se is not. You get the best results in P3D if you somehow manage to have as constant FPS as possible and if you get to this point, G-Sync basically becomes obsolete.

BTW: I think the greek guy is talking about hyper threading (HT), not "HP" (whatever HP should mean). And don't ask me why he thinks that 42FPS is a relevant FPS number for a 144Hz monitor...

Thank you for advice. Current installed driver version is 419.35. But I guess driver isn’t only cause. As I used to use 1080Ti with driver version 418's, and I'd experienced same problem. I tried every available driver but couldn’t solve the problem.

Since elegreco111 addressed HT thing, I experimented to disable it and I found P3D started with best FPS most of the time. Currently I add “affinity mask=250” entry and turn HT on as this configuration gets best result so far even though still caused little increased stutter after changing airport, and I noticed HT off got reduced disk access performance too. I'd never turned off HT and hadn't add affinity mask entry after P3D version 4, but affinity mask tuning still could increase P3D performance and I found there are lots of hot discussion about HT!

About FPS Limit, I tried FPS limit to 72 without changing CFG and HT on first. Then changing airport during session. Most of the time, FPS was same 72, but stutter increased. So, I think there were issues (bugs) on internal process of P3D, which need to be tuned.

I also found there was a little difference between FPS under 100' in G-synch and 72 limits without using G-synch. But I could feel some difference about fluidity between scenery that get over 100 consistently in G-synch and 72 limit without it. I like flying manually (No autopilot use), the more FPS (Fluidity) without stutters, the better and I also could enjoy benefit of high refresh rate display. But I’ll use 72 FPS limit too as I find it might get better result in some scenery area so that I could get almost constant FPS.

[AnkH]

I suggest an AM of 85 for your 4 cores + HT CPU. And remember: in my case, AM, HT on only works reasonable without a lot of stutters when using an internal frame limit. I know, it is cumbersome to test those things, but as soon as you found the Combo best suiting your rig, you will be happy for a longer time.