Why is my Framerate capped?

[NefariousKoel]

With Vsync on or off, my bridge view is capped at 20fps and binoculars,periscope,TBT @30.

There is practically no variance in it. Pegged at max. This didn't happen until after the 1.2 update. Before that I was running in the upper 30s for bridge view with all options enabled. I suspect I can still nearly hit that rate if not for the cap. What gives?

[Bilge_Rat]

probably because your CPU is the bottleneck and your video card is just sitting around waiting.

I have the same problem, my frames hover around 50 whether FSAA is at none or 4x, that is with a opteron 170 (2 ghz) and a 7900 GTX.

[DragonRR1]

1.2 introduced the ability to run in true high resolution in the 3D view and have driver forced AA.

If, for example, you were running at 1280x1024 before 1.2, the 3D view was running in (roughly) 1024x768 with no hardware AA. If you are now still running at 1280x1024 your 3D view is also running at 1280x1024 which puts more strain on your system. On top of that any forced hardware AA is also applied (if you had/have it on)

[SteamWake]

May I ask why does it matter ?

Since you cant see any difference at higher frame rates what does it matter ?

[AVGWarhawk]

15 FPS and higher, things should look pretty good. I usually do not have FPS running while I play. Lately I have, now I'm turning into a FPS watcher. For really no good reason either. I shut it off again, my game is smooth and plays fine. No sense in watching the numbers change.

[NefariousKoel]

If my processor were the bottleneck, then when I whipped the view around quickly, my fps would drop. It doesn't. It's might flash to 19 fps if I move the view fast enough with every option enabled but only for a fraction of a second.

It's stuck at 20 in 3D no matter what I do. I find it strange that periscope or TBT is also constantly max'd out at 30 fps.

I would agree with people saying the higher resolution of 1.2 has an effect... if the fps ever changed. It doesn't change. Hence, it's capped.

The only reason I complain is that I see the difference going from the 30 fps peri/tbt view to the 20 fps bridge view. Besides, 20 fps isn't very optimal. And they both obviously have a ceiling since they're stuck at that framerate but can go no higher.

[DragonRR1]

Originally Posted by NefariousKoel

If my processor were the bottleneck, then when I whipped the view around quickly, my fps would drop. It doesn't. It's might flash to 19 fps if I move the view fast enough with every option enabled but only for a fraction of a second.

It's stuck at 20 in 3D no matter what I do. I find it strange that periscope or TBT is also constantly max'd out at 30 fps.

I would agree with people saying the higher resolution of 1.2 has an effect... if the fps ever changed. It doesn't change. Hence, it's capped.

The only reason I complain is that I see the difference going from the 30 fps peri/tbt view to the 20 fps bridge view. Besides, 20 fps isn't very optimal. And they both obviously have a ceiling since they're stuck at that framerate but can go no higher.

There is something odd here but what exactly.. I don't know.. Can you list your:
CPU
Graphics card
Ram (amount)
Resolution you run at
Screen/monitor type
What graphical settings you have enabled.

In addition - assuming you have at least some effects turned on can you see what happens if you turn them off?
Can you also try running the game at the lowest resolution possible (assuming you don't already) and see what happens to fps then?

[Skipbo]

Sounds like your system is running very nearly like mine - with V-sync on. I have a 7900GS GFX card and a 3Ghz processor (HPT) with 2G RAM for what it's worth. My FPS were extremely variable without V-sync on plus after patch 1.2 and FSAA, had some tearing (mostly looking backward on the bridge) and minor stutters from the external camera view. Turning V-sync on (altered main.cfg in it's two locations plus 7900GS set to "use application pgm setting" plus SHIV menu vsync setting on) cured the graphics problems and limited my FPS to 30 in the interior views and about 20 from the external camera at Midway. This was with a screen refresh rate of 60HZ (SHIV menu and computer setting). I changed the refresh rate to 75HZ and am now capped at 38 FPS internal (1/2 refresh rate in 2D) and 25 FPS (1/3 refresh rate in 3D) at Midway on external camera. I chose Midway since there are lots of ships and planes to put a strain on the video card and processor. I cannot technically explain the precise ratios of FPS vs. screen refresh rates though, but maybe someone else can. Will at times drop to 19 FPS in some external camera views. Might check your video card setting since if it were set to "force on" (an option on the 7900GS) it might override the SHIV menu setting for V-sync. I can't tell a bit of difference visually if the FPS is above 15 or so though. If you are still positive that V-sync is off in your system, pls disregard the above! :p ............Skipbo

[Kant Schwimm]

This is a fairly long read but worth it if you really want to know about frame rates in pc games

"Frame rates are considered important in video games. The frame rate can make the difference between a game that is playable and one that is not. The first 3D first-person adventure game for a personal computer, 3D Monster Maze, had a frame rate of approximately 6 fps, and was still a success, being playable and addictive. In modern action-oriented games where players must visually track animated objects and react quickly, frame rates of approximately 25 to 30 fps are considered minimally acceptable, though this can vary significantly from game to game.
A culture of competition has arisen among game enthusiasts with regards to frame rates, with players striving to obtain the highest fps count possible. Indeed, many benchmarks released by the marketing departments of hardware manufacturers and published in hardware reviews focus on the fps measurement. Modern video cards, often featuring NVIDIA or ATI chipsets, can perform at over 160 fps on intensive games such as F.E.A.R. One single GeForce 8800 GTX has been reported to play F.E.A.R. at up to 386 fps (at a low resolution apparently).[citation needed] This does not apply to all games: some games apply a limit on the frame rate. For example, in the Grand Theft Auto series, Grand Theft Auto III and Grand Theft Auto: Vice City have a standard 30 fps (Grand Theft Auto: San Andreas runs at 25 fps) and this limit can only be removed at the cost of graphical and gameplay stability. It is also doubtful whether striving for such high frame rates is worthwhile. An average 17" monitor can reach 85 Hz, meaning that any performance reached by the game over 85 fps is discarded. For that reason it is not uncommon to limit the frame rate to the refresh rate of the monitor in a process called vertical synchronization. However, many players feel that not synchronizing every frame produces better in-game performance, at the cost of some "tearing" of the images.
It should also be noted that there is a rather large controversy over what is known as the "feel" of the game frame rate. It is argued that games with extremely high frame rates "feel" better and smoother than those that are just getting by. This is especially true in games such as a first-person shooter. There is often a noticeable choppiness perceived in most computer rendered video, despite it being above the flicker fusion frequency.
This choppiness is not a perceived flicker, but a perceived gap between the object in motion and its afterimage left in the eye from the last frame. A computer samples one point in time, then nothing is sampled until the next frame is rendered, so a visible gap can be seen between the moving object and its afterimage in the eye. Many driving games have this problem, like NASCAR 2005: Chase for the Cup for Xbox, and Gran Turismo 4. The polygon count in a frame may be too much to keep the game running smoothly for a second. The processing power needs to go to the polygon count and usually takes away the power from the framerate.
The reason computer rendered video has a noticeable afterimage separation problem and camera captured video does not is that a camera shutter interrupts the light two or three times for every film frame, thus exposing the film to 2 or 3 samples at different points in time. The light can also enter for the entire time the shutter is open, thus exposing the film to a continuous sample over this time. These multiple samples are naturally interpolated together on the same frame. This leads to a small amount of motion blur between one frame and the next which allows them to smoothly transition.
An example of afterimage separation can be seen when taking a quick 180 degree turn in a game in only 1 second. A still object in the game would render 60 times evenly on that 180 degree arc (at 60 Hz frame rate), and visibly this would separate the object and its afterimage by 3 degrees. A small object and its afterimage 3 degrees apart are quite noticeably separated on screen.
The solution to this problem would be to interpolate the extra frames together in the back-buffer (field multisampling), or simulate the motion blur seen by the human eye in the rendering engine. When vertical sync is enabled, video cards only output a maximum frame rate equal to the refresh rate of the monitor. All extra frames are dropped. When vertical sync is disabled, the video card is free to render frames as fast as it can, but the display of those rendered frames is still limited to the refresh rate of the monitor. For example, a card may render a game at 100 FPS on a monitor running 75 Hz refresh, but no more than 75 FPS can actually be displayed on screen.
High frame rates are also for creating performance "reserves" as certain elements of a game may be more GPU-intensive than others. While a game may achieve a fairly consistent 60 fps, the frame rate may drop below that during intensive scenes. A higher rendering frame rate may prevent a drop in screen frame rate."

Hope this helps

read more here..

http://en.wikipedia.org/wiki/Frames_per_second

[Skipbo]

Kant - Sure was helpful for me, thanks!

That article explains a lot of what is going on in my setup which was a bit mysterious to me previously. I'm seeing exactly HALF the refresh rate (having used 60HZ and 75 HZ) as my maximum 2D frame rate and one third for 3D though. I wonder if there is some video card (or other) setting that would allow getting the FPS equal to the refresh rate? Suspect I'm missing something key here, but there are a LOT of settings on my 7900GS. I found a guide to the settings via another post on SUBSIM and think I have several of them correct (triple buffering, multi/super sampling, etc.), but maybe I'm missing a critical one which would double my FPS? Not that I NEED it, but it would be NICE to optimize of course!

PS - The Nvidia Forceware settings information is at: http://www.tweakguides.com/NVFORCE_6.html

[SteamWake]

Originally Posted by Kant Schwimm

a camera shutter interrupts the light two or three times for every film frame,

What ?

[Kant Schwimm]

Originally Posted by SteamWake

What ?

I have know idea about that also:hmm:

[Bane]

Is V-sync enabled at the driver level?

[DragonRR1]

Originally Posted by Kant Schwimm

I have know idea about that also:hmm:

I've read about this before.. the way I understand it is:
Basically it's like taking a photo 2 or 3 times on a single section of film. So, for example, if you looked at the single frame of a car moving left to right AND during that frame the car moved entirely across the photo you would actually see 3 images of the car overlaid on top of each other (the first on the right, the second in the middle and the third on the left) with motion blur in between.. This is one reason why 25 fps is OK for TV/Films etc is because you are (sort of) getting 2 or 3x25fps.. On a computer you don't get these in between frames.. each frame is "perfect".. I really hope that makes sense

The only problem I have with the above is that if you did only one exposure per frame you would get the same motion blur effect across the frame. I guess you would lose some of the detail due to the slower shutter speed....

[RickC Sniper]

My framerates are capped at exactly half my monitor rate. My monitor's native is 1680x1050 x 60hz and this game runs at 30 fps. (in 3d, not 2d) In the 2D screens fps shoots way up.

I have no idea why this is. Vsync is turned on. Thought fps would be locked in at 60fps.

Intel E6600 duo
ATI X1950XTX 512mb cat 7.3 drivers
2 gig ram