Hey LameLefty,
sorry for the late response.
First of all, I would recommend turning off any OC of your hardware. OC can cause CTD´s.
It is kinda unlucky, we have to turn off our CPU Auto Overclocks or GPU Overclocks, cause it´s just state of the art nowadays. Losing up to 10FPS is hard to accept, but there are some performance improvements you could get them back maybe.
Here´s a good guide about performance, maybe you could get your 10 FPS back.
Performance Guide
[HOW-TO] Graphics Settings and Performance Guide (8/18/2020)
The ATC CTD´s are common since Patch 1.8.3.0 . Unlucky, I couldn´t found a possible solution. There are only the things you already tried to do, so I guess the best thing is, don´t use ATC and wait until ASOBO will patch this bug.
Many users already reported that issue, but it is still a good thing to submit a Ticket at Zendesk about the issue.
Have a nice day!
Marc / Epic Primus