For anyone in PTB experiencing sudden low or low & locked FPS

When I first fired up the PTB my FPS in all menus, lobby and inital gameplay until I was hooked by the new killer for the first time was normal 60FPS with no dips and rock steady frametimes.

Then while on hook and afterwards it dropped to 25-35 and stayed there for the most part until I was alone doing a gen and it slowly crept up to the 50 range. It dropped when others were on screen back to 25-35 and stayed this way throughout the match and continued after the match even in the menus.

I checked multiple times while this was happening and GPU/CPU usage both under 50% and temps of both were 40-50c which is normal, ram usage was normal, basically 0-1% disk activity.

After that match was over I checked over all of my settings and nothing was changed. I started up DBD again and this time even in menus I would hit 30FPS and it wouldn't go higher at all, indicating to me that V-Sync was enabled which normally I have disabled via GameUserSettings.ini so I checked my ini but it was set to disabled still.

After a few minutes of #########'ing I remembered that G-Sync disables itself under 36FPS and a side effect of this is that the "V-Sync" option in NVCPL (which should be set to "On"/"Forced On" when using G-Sync for it to work correctly because while using G-Sync it does not actually control V-Sync) reverts back to actually controling "V-Sync" so it forces V-Sync on makes things wonky during that game as well as when you start the game up next time and since V-Sync is forced on and doesn't allow the game to go over 36FPS which would allow G-Sync to re-enable itself I was stuck @ 30FPS with V-Sync on & G-Sync off.

TLDR: While in game in settings menu switching from "low" to any other graphic setting and then back to "low" instantly solved this issue, even though it did not change any of the settings that are visable in GameUserSettings.ini. I re-created this issue multiple times on various maps with same results each time.