I'm not sure if this will apply to everyone, but I was experiencing heavy frame buffer drops (dropping as low as 13 fps) while previewing in OBS in both updates 6.2.6 and 6.2.7 even after a completely clean install (manually removing leftover profile and registry files). The issue only occurred while Precision XOC was running. OBS would close if i closed out Precision XOC while both were running. Problem ceased either while XOC was not running and after rolling back to 6.2.3. 
 
I have yet to see this posted here in the forums so I wanted to make sure the word got out. This could be a big problem for live streaming using OBS.
 
Hardware Specs:
CPU = Intel i7 7700k OC @4.8 GHz
GPU = EVGA GTX 1080 Ti SC2
RAM = 32 GB Corsair Vengeance RGB @ 3000 MHz
MOBO = Asus Maximus Hero IX Z270
PSU = Cooler Master V850
COOLER = NZXT Kraken x52
STORAGE = 256 GB Samsung 960 EVO M.2 SSD
= 2 x 500 GB Samsung 850 EVO SSD
= 3 TB Seagate HDD 7200 RPM