My LFS worked fine but after i installed new update 0.6J it went all wrong.
Framerate jumps from 100 to about 50.
It's unbearable stuttering to play.
I Have I5 2500k and radeon hd 7870 so the problem can't be my hardware.
Os is Windows 10 but it worked fine with 0.6H so i don't it's that either.
Please help!!

Maybe other programs that are killing your ram? Google chrome use some ...

Sorry, your CPU is too fast for LFS now. You'll have to buy a slower one.

Most probably your GPU is going into an energy saving mode because it's not utilized enough. With nvidia you can force a "maximum performance" profile, maybe you can do that too with ati?

Dirt rally and assetto corsa works fine, LFS is only game that has those kind of glitches. I have 16GB of RAM so i dont think that's the case...
Only program (other than windows's own programs) i have on in the backround is AXTU to manage my fans... I belive this problem came with the new update of LFS...

Forgot to mention that the framerate jump is constant, it is 100 for about 2 or 3 seconds and drops to about 50 or under for about half a second, and then back to 100 for 2 or 3 and again and again... So the game is now totally unplayable.

test - vsync off and disable frame limit

didn't help at all. i have tried almost everythin i can think of.

Quote from Badcarma :

didn't help at all. i have tried almost everythin i can think of.

Then try everything you can think of!

Stop speculating and get some data! Play LFS with some gpu/cpu/ram monitoring tools running in the background such as MSI Afterburner or GPU-Z for GPU and the Resource Monitor (or the good old Task Manager) for CPU.

Then it might be easier to spot the bottleneck.

This looks a lot like the CPU governor mishandling power management and sending the CPU into some power saving mode even when it shouldn't. I don't know what tool on Windows can track CPU's C and P states but I suppose this is something you should look into. There have also been reports of the Hyper-V hypervisor causing serious performance problems with LFS.

Quote from Badcarma :

I Have I5 2500k and radeon hd 7870 so the problem can't be my hardware.

I would look at reinstalling/updating drivers.

You could even make a new seperate LFS installation and test if that corrects the issue especially since you said other games play fine

LFS may or may not be the problem, but without more information it's basically guess and check right now.

Found the problem! Or sort of... When i change the resolution down, and back to 1920x1080 @ 59Hz the game starts to work as normal. But i have to do it every time i start the game.

LFS makes use of Direct3D9 Ex since 0.6J, perhaps that triggered a bug in the graphics driver, especially when you are on Win10 where the drivers might be a bit glitchy. Unless there is an update available you might want to talk to AMD's techsupp.

I have the latest driver available. So there's nothing i can do at the moment, but to wait for the bugfix or a new set of drivers,
if the driver glitch is the case.
If anyone else is experiencing something similiar i'd like to hear about it, just to confirm that it's nothing that is failing in my system...

Disable "sleep every frame" from misc section in LFS settings, it doubled my fps from 300 to 600

I can confirm the same thing. I have nVidia GeForce GT 755M. It usually gives me FPS 300+- smoothly, but I've limited FPS to 100 (why push the card if 100 gets the job done). Everything's set at max and it worked well. The FPS used to stay between 90 and 100 and was smooth as Platonic Silk.

After the update, the FPS stays flat at 100, but there is noticable micro to minor stuttering. Sleep every frame turned to off doesn't remedy the problem. There's still stuttering. What does the "Maximum Buffer Frame" function do? Use 1, 2 or 0? Please suggest what options to turn off for computers that can handle LFS as it was just fine.

Power plans aren't causing this problem in my case. Maybe, someone can suggest what changes to put in the nVidia Control Center profile for LFS. Since I'm not using SLI with LFS, it's set to single GPU. Other than that, everything is at its default or set to use LFS' settings.

Specs:

i7 4702MQ Quad-Core
GT 755M
GT 755M
SLI is not used with LFS
Ram 8 GB
SSHD 1 TB with 8 GB SSD Cache
512 kbps internet.

If LFS stutters on this machine, then something is amiss. rFactor runs fine, since it's also a dx9 game, so does GTR2.

Forgot to mention Win 8.1 x64

I have the same problem .. Before updating all is well with Patch J came easily weigh stutter and freeze for 1 second game ... FPS is good from 300-500 FPS .. It's annoying and it spoils the game ... Thanks in advance for solving

nVidia update 355.60 was released yesterday; installed it and it looks like the problem is solved, though I haven't tested LFS thoroughly. I will report back when it is certain. nVidia users should update their drivers.

Quote from hereticlohani :

nVidia update 355.60 was released yesterday; installed it and it looks like the problem is solved, though I haven't tested LFS thoroughly. I will report back when it is certain. nVidia users should update their drivers.

Quote from edge3147 :

I would look at reinstalling/updating drivers.

You could even make a new seperate LFS installation and test if that corrects the issue especially since you said other games play fine

Try a clean LFS install before you blame LFS again please.

I installed the new driver and seemed to improve, but tonight I'll try .. driver version 355.81 think .. and new installation LFS've already tried and he was still the same problem .. I'll see you when I get home today

correction For Nvidia Geforce 8800GTS new driver is 341.81

Try reinstalling DirectX 9.0c and lower.

http://www.microsoft.com/en-us/download/details.aspx?id=35