AC: Stuttering reduction

What can a user do to reduce or eliminate stuttering even in practice runs where their are no other cars on the track?

With Lotus F1 on Monza track I sometimes get as many as 6 stutters per lap, sometimes its 0 which is great.


What is the key cause of stuttering when running AC local vs MP which involves network response time as well as AC MP implementation?

Background:

My system: CPU: Intel i7-4770K Haswell 3.5GHz (some small amount overclocking was installed from Main Performance)
Video: NVIDIA | EVGA GeForce GTX 780Ti to 3 ASUS VE278Q 27” monitors 85hz refresh


I use a SSD memory for the AC install (The SSD is my C: drive)
My cpu usage is about 26% when AC is running. Processor Affinity shows all checked (0 to 8), Priority=Normal,
window resource monitor shows the cpus are getting used and none are any where near 100%, more like 40-50% and there are graphics showing PARKED cpus.

I turned off the car interior controllable items: no wheel, no driver arms.
I set Frame Limit to match my monitor max at 85.
FRAPS shows FPS will dip to 67 in some corners.
I tried reducing smoke generation and mirror resolution, I turned blur off completely.
I have not turn off HDR yet.
I have not tried to us msconfig and kill all background processes. I typically have firefox running in the background
which is the larger memory user (then Spyhunter4, explorer, LCore, office.bin, Steam....)
I have not tried to ALT-TAB out of AC when I see stuttering to see what is running with the resource monitor.
After I ran the resource monitor and looked at the CPU tab and saw a number of PARKED cpus I downloaded and ran a disable parking utility (edits the registry). This seems to have helped. Any problem with doing this?

http://coderbag.com/Programming-C/CPU-core-parking-manager

http://www.coderbag.com/Programming-C/Disable-CPU-Core-Parking-Utility

AC settings: Fullscreen Rendering ON | Triple Screen ON (6065x1080) | Vsync - OFF | Frame Limit - 85 | Aniso x 8 | AA x 4 | FXAA x 3 | Shadows -Low | World Detail - Maximum | HDR Color Sat On @ 92%| Smoke Generation – Low||Smoke in Mirrors OFF| Motion Blur - OFF | Mirror Resolution High| CubeMaps at Low | Faces per Frame - 4
 
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Hyperthreading isn't helping, it never does in games. The only way to disable hyperthreading is to go into the BIOS and turn it off. Hyperthreading doesn't usually cause any issues but it can cause stuttering, however in this case, I'm inclined to believe the real issue is simply the 780ti can't keep up at that resolution. I know that may sound crazy to some people using lesser video cards, but AC is a very very graphic intensive game with even half the details turned on. I only use a single monitor but I play at 2560x1600 resolution which is a lot more pixels than 1080p and even with two 780's in SLI, I do wonder if I have enough graphics muscle to play with triples at the max detail, but I can safely say, my two overclocked 780's in SLI is a good 60-70% faster than a single 780ti so in Rick's case if this game is a true love for him and he really wants to get the most out of it, he's probably going to have to upgrade and get another video card to run in SLI with that setup if things like stuttering bother him which it seems they do. I get no stutters at almost full graphic detail, but again, I'm not running the resolution he is and I have two cards. I started with a single overclocked 780 and AC is the single reason why I bought a second 780. I loved the game that much that I wanted the best possible experience so I bought two cards if that's what it takes.
 
Blkout or Karl,
Video ram on 780ti has 3Gb,
Sorry I am not smart enough to know how to check usage of it.
Can you advise on how to check the usage?
Can you advise on how to verify overclocking amount on the cpu and gpu?

I will try the 2xAA setting
You can monitor memory usage of your graphics card with msi afterburner:
http://www.computerbase.de/downloads/system/grafikkarten/msi-afterburner/72777/
click big blue button on top

click detach to show more info after you run the program


to adjust monitoring items, go to settings (at bottom right)


Info regarding memory usage:
http://www.racedepartment.com/forum...-and-resource-usage-of-aa-and-af-in-ac.86798/
 
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I'm about 99% certain the video card memory isn't an issue. 3GB has still been proven to be more than enough even for triple screens and 4k resolutions today. About the only game so far to date that has really taken advantage of 3GB or more of video memory is Watch Dogs using Ultra texture setting. That game can actually cause stuttering on cards with less than 4Gb of video memory using ultra textures but Ubisoft is working on that issue as speak with an upcoming patch.
 
Before I saw your memo I ran a few laps with it running.
I assume you ment look at the differ core cpu %
GPU peaks 86 but average is 60-70


Bye the way, 1st 5 laps of practice with Afterburner running. No stutter.
This is with no changes so far. no vsync, 85fps, no latency 1....
BUT quick race, about 4 per lap. Down from the 7 last night.

Then I turned in game vsync on. Little worse 8 stutters and 1 made me jerk and crash. Cores dont look that busy.

Main Performance said ?We only overclock very mildly, we actually use the default BIOS overclock"

I will turn off temp an other items in Afterburner now that I am getting learning about it.

Marty, Yes I have alot to learn but am willing and able with all the help I am getting for all of you.
 

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I'm about 99% certain the video card memory isn't an issue. 3GB has still been proven to be more than enough even for triple screens and 4k resolutions today. About the only game so far to date that has really taken advantage of 3GB or more of video memory is Watch Dogs using Ultra texture setting. That game can actually cause stuttering on cards with less than 4Gb of video memory using ultra textures but Ubisoft is working on that issue as speak with an upcoming patch.
Memory on graphic cards is used effectively. If more is available to be occupied, it will be and vice versa. I can't say for certain, if this is his problem, tho.

And Rick, the cpu usage you see in the taks manager is not acurate while playing games or running it on a day to day basis. You see real values like 100% usage almost exclusively from benchmarking programs, exempli gratia prime95 and cinebench. Also, an i7 Haswell should eat AC for breakfast even with tripplets this cpu is overkill.
Have you tried reducing faces per frame from 4 to a lower setting (1)?
Edit: you did already, just saw post #8

How much RAM you have?
 
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Georg, 16G ram. Yes I have faces to 1

Others that have been helping me:
GREAT NEWS. After changing Latency to 1 and in game vsync on
NO stutters for 5 race laps.
Slight few pixel tears on the Monza poles back side.
This is GOOD enough, image is very nice. FPS solid at 85. GPU running at 70 average, memory clock is 3500
Thanks for everyones patience and help.
Afterbuner attached FYI.
 

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Hyperthreading isn't helping, it never does in games. The only way to disable hyperthreading is to go into the BIOS and turn it off. Hyperthreading doesn't usually cause any issues but it can cause stuttering, however in this case, I'm inclined to believe the real issue is simply the 780ti can't keep up at that resolution. I know that may sound crazy to some people using lesser video cards, but AC is a very very graphic intensive game with even half the details turned on. I only use a single monitor but I play at 2560x1600 resolution which is a lot more pixels than 1080p and even with two 780's in SLI, I do wonder if I have enough graphics muscle to play with triples at the max detail, but I can safely say, my two overclocked 780's in SLI is a good 60-70% faster than a single 780ti so in Rick's case if this game is a true love for him and he really wants to get the most out of it, he's probably going to have to upgrade and get another video card to run in SLI with that setup if things like stuttering bother him which it seems they do. I get no stutters at almost full graphic detail, but again, I'm not running the resolution he is and I have two cards. I started with a single overclocked 780 and AC is the single reason why I bought a second 780. I loved the game that much that I wanted the best possible experience so I bought two cards if that's what it takes.
Great job Rick in getting your afterburner working and getting your game running smoother. Vsync definitely helps.
And don't do anything crazy like getting another GTX 780 until you learn how to squeeze out another 10 to 15% with the great set up that you currently have. Once you get the maximum out of your system you can decide if you need to SLI or not.
Triple screens... u lucky guy u.. :)
 
Marty,

Well I spoke too soon, still have some stutter. I dont know but I must have had a LUCKY race with 0 of them, I was staying back from the other cars so I could watch for the stutters, must have been a smaller amount of graphics work to do. Wish I had some way of knowing exactly what causes it and the fix. Maybe its just the busy AC code. I get a single stutter a bump in the track, or going into a dark shadow area, and also in fast corners (just when you dont want a stutter). Theory: I went from 0 stutters before lunch, with no settings change to about 5 / lap after. So clearly this means "stop eating lunch".!!

Afterburner clearly shows them when they happen so I can count them
and record the results given the settings change.

After the post lunch race I moved Frame count to 200 and stutters dropped to 1 or 2stutters per lap and the GPU went 100% busy of course.

I will keep poking and testing like you suggested. Lots for a new PC simracer to learn.

Yes my IBM retirement checks goes to some nice toys and its alot cheaper than tracking my IS-F.
 

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I got AC via steam and I dont see a place to specify the install path or a way to uninstall and reinstall via steam. I have to study/search to find out how
to implement your suggestions.

I have been watching resource (CPU) monitor and now Afterburner and before in the last 2 races I did kill firefox just because it was using the biggest chunk of memory.
I dont see much activity in the background but it might be worth a
try to kill of almost everything and see what happens.
I need to work on this and see if this is causes by a specific process before I do anything else.
I killed off all the tasks that were not really needed and still have about 2 - 3 stutters per lap but at least its not 6 or 7.
 
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Great job Rick in getting your afterburner working and getting your game running smoother. Vsync definitely helps.
And don't do anything crazy like getting another GTX 780 until you learn how to squeeze out another 10 to 15% with the great set up that you currently have. Once you get the maximum out of your system you can decide if you need to SLI or not.
Triple screens... u lucky guy u.. :)

You can squeeze out 10% more performance by overclocking and tweaking for hours or days or you can get two video cards and get 80% more performance without even doing anything...
 
Marty,

Well I spoke too soon, still have some stutter. I dont know but I must have had a LUCKY race with 0 of them, I was staying back from the other cars so I could watch for the stutters, must have been a smaller amount of graphics work to do. Wish I had some way of knowing exactly what causes it and the fix. Maybe its just the busy AC code. I get a single stutter a bump in the track, or going into a dark shadow area, and also in fast corners (just when you dont want a stutter). Theory: I went from 0 stutters before lunch, with no settings change to about 5 / lap after. So clearly this means "stop eating lunch".!!

Afterburner clearly shows them when they happen so I can count them
and record the results given the settings change.

After the post lunch race I moved Frame count to 200 and stutters dropped to 1 or 2stutters per lap and the GPU went 100% busy of course.

I will keep poking and testing like you suggested. Lots for a new PC simracer to learn.

Yes my IBM retirement checks goes to some nice toys and its alot cheaper than tracking my IS-F.
Hey Rick

I just looked at your afterburner screen shot. You are maxing out your GPU to the max. Was that with Vsync off??? If it wasnt then ya, you will need to tone down some of your graphics settings. If you cap your frames to 60 Hz with Vsync On, you might be able to give your GPU more breathing room and therefore get a smoother game play. Also looking at your CPU temps. its begging to be overclocked. only hitting 55 Degrees C.
 
The image you looked at has 2 races with different settings of Frame Limit (85 and then 200) I wanted to see if this changed the stutter rate and I did. at 85 the GPU was only 70 % and then at 200fps GPU jumps to 100%
Vsync ON in both cases. Thanks for the poke on overclocking. I will study up on it.
 
Well I have some interesting testing that you might like to see.

I left
MAXIMUM_FRAME_LATENCY=1
during the following tests. I left all the Nvidia settings the same.
AF 16x, FXAA off, AA gamma On, AA 4x, AA Transparency off, and Nvidia vertical sync Off.
In game Vertical Sync ON.

So the plan was just change the in game graphic settings.

I decided to try 4 races, each 5 laps, Lotus Exos 125 S1, Monza 66, 9 cars, I would drive in the back of the pack to have a common position. 1st race: will all settings to the lowest value. 2nd race: all settings to the max value (I did not change HDR, which was disabled, in theory the lower stutter setting, just missed changing this setting in race 2). Bottom line, same number of stutters in both, about 18. ????? hmmm.

I could not believe it but new it was about the same as I was driving. I recorded both with Afterburner. I also had Resource monitor showing process average CPU at the very end.

Cleary the max out settings put the GPU to the max (the top trace shows mostly at 100% in the 2nd race vs about 50%). Also the 1st race was at 85fps except dropping to 72fps during the stutters. In the 2nd race the max setting resulted in about 50fps, showing it was a struggle to implement the max settings. Bye the way, when I say max I mean it, 16x AF, 8x AA Shadow res high, max world res, ultra smoke, smoke in mirrors, high mirror res and high quality, cubemap high, faces per frame 6.

I could clearly see the anti aliasing helps and really liked the realistic smoke.

So, go figure why the same stutter count.????

These stutters always happen in about the same places in the track. Not exactly but close. Just after the start/finish line (bumps), 1st corner before or after (50%)
3rd and 4th tight corner.(60%) just past the overpass or the 5th corner (shadow, bumps),
and last corner (before or after it).

Next I went to single screen 1920x1080, thinking that this is 30% of the load but guess what. Stutter count a little worse. 3rd race max settings stutter count 19 (higher by 1) and the 4th race with settings off or low stutter was highest at 24.

If nothing else I am getting alot of practice and learning to see what the settings change in the image.

Next then I changed to GSCE, Interlogos Historic (for speed of background) and used the V12 car and 9 other v12. I used max settings for details. Triple monitors for the largest graphics load. Drove fast. Laps were shorter but close enough. Bottom line: At most a total of 2 stutters in the 1st race and 1 in the 2nd. 10x better.
Afterburner attached.
FPS was around 200 (often pegged), GPU was very busy average 80 with 100% peaks. Stutters show up as fps would drop from 200 to 132. And then the surprise: Only making heavy use of 2 of the cores CPUs. My I7 was coasting.
 

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I get the odd freeze just for a split second, I found it helped if you change the priority in task manager from normal to high, just start Assetto, bring up task manager and go to Asserto corsa, right click, set priority, change to high, close task manager.
 
I don't understand some of these solutions that require leaving game, setting prioirties, etc. I don't have to do any of that to get a solid experience without stutters. I don't think the game devs want people to have to do that. I believe the stutters are possibly related to hyperthreading or not enough graphics power for the resolution being run. Most other solutions have been tried and had no effect.
 
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Rick, I have one more suggestion and I hope I didn't miss this somewhere earlier in the thread. Have you tried just running the game on a single monitor and see if the stutters remain? Resoution and graphics workload would be drastically reduced. I also recommend when you try it, to disable vync so that you will get as many frames per second as possible. This would give you a better idea if this issue is framerate related. I suspect your framerate on a single 1920x1080 monitor should be around 150-200fps which should be a very smooth experience unless you have another issue somewhere else. I know you want to run triples, but this would be a necessary test to see if its a graphics processing issue, which might indicate that you need a second video card if it runs smoothly on a single monitor.

Finally, I applaud your tenacity and willingness to keep trying. Many people would have given up by now.
 
More hints. I was working on system issues today. Doing full memory check, dskchk and several warm restarts and cold starts. I happen to notice I had fewer background processes. See attached taskmanager list vs the one in the last post. WELL I ran AC 5 laps with medium high graphic settings and NO ST
 

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