This morning I was flying the Xtreme Prototypes Lear 25 from Prague to Berlin. I use ChasePlane and have various views configured which include two from the passenger seats just forward of the wings looking left and right.

Whilst the pilot and other cockpit views easily maintained 30fps that dropped to 15 when viewing those two pax views. That was in full-screen mode. Switching to Windowed and the problem disappeared and 30fps was constant.

I've been flying this plane for ages and this was a new problem. What had changed to cause it? And why only in full-screen view?

The answer is Triple Buffering. I had turned it off a couple of weeks ago following a discussion where some had said it reduces stutters for them. It's been off since then and has been fine for nearly all my views. But this particular view was severely affected by TB being turned off.

Turning it back on instantly resolved the problem so if you have a similar situation with internal views check your TB setting. In some situations it makes a big difference.

If I have Vsync on then I always have TB on, because I find that otherwise it almost always tanks my frame rates, internal or external. I always assumed it was a driver bug!

Neil,

I kept an open mind and decided to try it. But as you say it does have repurcussions. Whether it's the driver or something in P3D I haven't a clue. I'm just pleased it was a nice simple problem to resolve.

It's also a classic case of settings being highly dependent on specific rigs.  I had gone thru all of V4 flying finding vsync on and TB on were the best.  Then in V5 TB off was smoother.  Although it was only in the last couple weeks I found vsync off entirely and instead using NCP frame limiter is good.  I used to manually change my refresh rate from 60 to 30 in NCP when flying.  Not a big chore, but still a PIA.   At one time I had a script do this for me.  The one consistent truth for me is my setup is always changing.  Usually with each update. 

6 minutes ago, micstatic said:

It's also a classic case of settings being highly dependent on specific rigs

Or specific aircraft. This is something that only affects the Lear 25 and the views I have setup. If in doubt, experiment.

1 hour ago, micstatic said:

Then in V5 TB off was smoother.

Same on my system.

3 hours ago, micstatic said:

Then in V5 TB off was smoother. 

Has always been the case for me, including V4.

What you guys can tell me about Hyper Threading Off in BIOS? It worth it? 

Edited July 8, 20214 yr by Druce

29 minutes ago, Druce said:

What you guys can tell me about Hyper Threading Off in BIOS? It worth it? 

Let's not hijack this thread with another HT discussion...there's plenty already said about HT in other threads here.

On 7/8/2021 at 1:03 PM, Ray Proudfoot said:

This morning I was flying the Xtreme Prototypes Lear 25 from Prague to Berlin. I use ChasePlane and have various views configured which include two from the passenger seats just forward of the wings looking left and right.

Whilst the pilot and other cockpit views easily maintained 30fps that dropped to 15 when viewing those two pax views. That was in full-screen mode. Switching to Windowed and the problem disappeared and 30fps was constant.

I've been flying this plane for ages and this was a new problem. What had changed to cause it? And why only in full-screen view?

The answer is Triple Buffering. I had turned it off a couple of weeks ago following a discussion where some had said it reduces stutters for them. It's been off since then and has been fine for nearly all my views. But this particular view was severely affected by TB being turned off.

Turning it back on instantly resolved the problem so if you have a similar situation with internal views check your TB setting. In some situations it makes a big difference.

I also experienced the phenomenon that you have described a few times. It looks like whenever your target frame rate cannot be maintained in the given situation (regardless of whether you limit the FPS in-sim by the slider or via Vsync), the FPS is automatically halved (or divided further by an integer) with triple buffering disabled until your scenario provides enough headroom for your desired FPS. Any benefits to this?  The only one I can think of is that it avoids stutters that emerge due to the FPS not being in sync with a multiple integer of the monitor refresh rate, but it comes at a huge cost for the FPS. The other benefit is that due to the lower FPS, it naturally reduces the load (=temperatures) on the CPU and GPU during the high-stress situations.

Anyway, activating triple buffering eliminates this behavior. Whether it's intended or a bug I don't know, but in the past versions, I never saw any difference between triple buffering on and off. Did you?

3 hours ago, Afterburner said:

Anyway, activating triple buffering eliminates this behavior. Whether it's intended or a bug I don't know, but in the past versions, I never saw any difference between triple buffering on and off. Did you?

It’s a while ago so I had a quick flight from Manchester to Dublin in the Lear this afternoon. First flight with these new drivers installed using NVCleanstall.

As the aircraft climbed through the cloud I checked with TB on and off. 30fps was maintained in both. Maybe cloud wasn’t thick enough or maybe the drivers and NVCleanstall are the reason.

For some odd reason, I don't get any stutters or loss of FPS anymore.  My P3D has been running absolutely perfect the last few months.I did upgrade my machine to a new PSU recently.  I can't imagine that helped, but maybe my GPU needed a little extra room to breathe.  I don't want to touch a thing.  My biggest improvement came when I limited the refresh rate on my monitors to 30.  My FPS just stay at 30 and never move more than one or two off of that.  I probably just jinxed myself!

@Deltaguy, relocate to Heathrow or Atlanta and set AIG aircraft to max. That works my system. But you haven’t listed your system. 😉

9 hours ago, Ray Proudfoot said:

@Deltaguy, relocate to Heathrow or Atlanta and set AIG aircraft to max. That works my system. But you haven’t listed your system. 😉

I did just that (EGLL) and on or off TB / Vsync made no difference on my system. On ground it hovered around 18 fps. (with fairly high settings which I use on less detailed airports).

2 hours ago, IanHarrison said:

I did just that (EGLL) and on or off TB / Vsync made no difference on my system. On ground it hovered around 18 fps. (with fairly high settings which I use on less detailed airports).

VSync will limit fps to 30 where it’s greater than 30. It does nothing when <30.