Game refuses to use CPU 1 and 2 except when tabbed out

[SalamenceFury]

I'm literally pulling my hair out at this.

 

Since a while ago (I suspect a week or two after After Hours) the game has been extremely slow to the point I'm finding it nauseating. The game refuses to use CPU 1 and 2, putting all the load on CPU 0 and 3 while the other two stay at 25% usage or less. This also causes the game to get to very low frame rates. However, once I tab out of the game for whatever reason, the CPU 1 and 2 start receiving the load from GTA V and I get a large FPS boost. I have no idea what's going on, I've reverted all the way to driver 388.13 without PhysX and this sh*t hasn't been fixed or showed any signs of going away. This happens both in Online and Single Player.

 

https://i.imgur.com/nW94Ikq.png

 

The dips on CPU 1 and 2 happen when the game is highlighted and I'm actively playing. I've tried all the following things:

 

- Disabling all non-MS services

- Reverting to driver 388.13 all the way from 399.01

- Reverting my CPU overclock

- Removing PhysX

- Putting GTA V to Real Time CPU priority

- Scanning the system

- Deleting sh*t from my drive

- Verifying GTA V

 

Only thing I haven't tried is a full system reset which I'm not planning to do soon but might have to depending of how this sh*t happens. I've tried Rockstar Support with no dice. I don't know if this is normal game behavior or not.