http://steamcommunity.com/app/271590/discussions/0/611703999968097067/?l=english

ลองเข้าไปอ่านดูครับ  เห็นใช้พวก Xeon แล้วมีปัญหาเหมือนกัน ขึ้น error มาเหมือนกัน

I disabled hyper threading and it worked for me.

Succes !

Well I have some good news.
My system has 2x E5-2698 v3 processors, 32 cores / 64 threads.

No matter what I did I would receive that ERR_SYS_THREAD.
Even if I disabled 1 CPU.

Here is my fixed that worked for me.

I fire up the game with the Steam Launcher.
It will error out with ERR_SYS_THREAD

I then bring up the task manager and select GTA V Launcher.
Right click and drop down to Affinity.
I deselect all cores.
Now I enable CPU 0 (Node0) through CPU 0 (Node 8)
I cannot use any more than that as I will get that error.

The I hit retry on the GTA V Launcher and the game will work.

It seems GTA V is not NUMA aware and limited by the number of threads it can use.
Users with different CPUs might have to set Affinity slightly different than what I did,
I somehow do not think they will ever do a patch for this because I am such a rare user, but who knows.