Excessive, unplayable FPS after october update

So I decided to hop onto Garry’s Mod since a bit and I get greeted with… well, less than a single frame per second, occasionally 2. Not even joking.
I checked the task manager and GMod is only using 1-2% of CPU at any given time, unless loading a map.

No relevant console errors, and nothing else I can think of that would cause it.

CPU is Pentium G3258,
GPU is EVGA GTX 960
8gb RAM
on Windows 10

[editline]29th October 2016[/editline]

Only seems to be happening in multiplayer on any server, even empty ones and local servers.

[editline]29th October 2016[/editline]

hl2.exe also crashes (has stopped working) when trying to quit normally while lagging. this doesn’t happen all the time though
Minidump located here: http://dumps.metastruct.uk.to/dumper.py?dump=hl2_161028_crash_2016_10_30T4_29_36C0.mdmp

[editline]29th October 2016[/editline]

validation does nothing

Any workshop subscriptions?

Yeah, a good few.
Servers I play on also have workshop downloads
I’ll try running with -noworkshop

[editline]29th October 2016[/editline]

No good

Exit Discord or Overwolf.

another reason to use mumble instead