CS:GO Frame rate issues

I've looked everywhere without finding answers that actually work so I thought, i'd post here. I've logged 700 hours in CSGO, most of which without problems, however quite recently (Maybe 3 or 4 months ago) I've had some odd FPS issues. My game usually runs at about 140-160 FPS however it sometimes drops below 60 and hangs at 40 until I alt tab, or restart the game. Its quite frustrating when it happens and I have yet to find a fix for it. Thanks for reading

PC SPECS & IN GAME SETTINGS

GPU: Nvidia GT 750M
CPU: Intel i7 -4700MQ @ 2.40GHz
Memory: 8 GBs
OS: Windows 8.1

In game settings
Resolution 1440 by 1080p 4:3 stretched (I've changed res many times to see if that was causing an issue, nothing different happens)
Global shadow quality : Low
Model/texture detail: Low
Effect detail: Low
Shader detail: High (I've changed to low before and it seems to fix it but only for about 2 minutes before is craps out again)
Multicore Rendering: Enabled
MSAA 2X
Anisotropic Filtering 2x
FXAA: Disabled
Vsync: Disabled
Motion blur: Disabled

EDIT** Multicore rendering seemed to be the issue, holy shit, thanks!

Try to disable multicore rendering, people have reported it fixing the issue on laptops. Sure the fps might get a bit lower but it shouldn't hang like it does now.

Disabling multicore should help, and I would also disable MSAA and go with FXAA.

This may be an issue due to the updates that have been rolling out. Or something else. What maps do you get this on, some maps are better optimized than others.

Will do, thanks I've never heard of that even being an issue

Map choice doesn't seem to play a difference in the fps drops as far as my knowledge. Will go with FXAA, thanks :)

1440x1080? you mean 1440x900?

Also, set proper launch options.

-threads 4
-high/realtime (depending on which you want)
-tick 128

Also check to ensure all of your CPU cores are unparked. With my hex core AMD I got a massive spike of like 40-50 extra fps by ensuring my cores were unparked.

if you are playing Comp games, turn all filtering off. It will help.

No, I mean 1440x1080 via launch options (look it up makes the game look reasonably nice at 4:3) Also, Got all the launch options and i've made sure to unpark my cores.

Just played a full comp game on mirage with not a single drop..I love youuuuuuu

I could never play comp with that res =O. 1280x960 is the way to go. I find it the best mix of bigger models to looks.

I've done 960, I think its okay, but menus start to annoy me at lower res

that is a drawback, but I dont spend much time in those.

Thats true I guess.

Glad I was able to help. I did a lot of messing with the graphics settings to get CS:GO to run at 60-65FPS on my terrible HD4600 so I know something about the way each setting affects FPS.

Im surprised you had issues. What kind of processor do you have. The game is a source engine game, so it should rely mostly on CPU.

i7-4700MQ, there is utterly no CPU bottleneck, but because Intel sucks with iGPUs, it struggles. So plenty of things got turned down.

Ah