Since the 126.96.36.199.77455 patch, I've been having a hell of a time with the ingame shaders. Pre-patch, I'd run the game with an average of 68fps, going as high as as 97 and as low as 50 when everything was going crazy. However, with the same settings, I've been getting an average 38fps, dips down to 8, and spikes only go as high as 52 when I'm lucky. I've noticed this gets particularly bad if I look in the direction of objective D on coop security on Refinery. If we have to defend that objective, I'm pretty much useless to the team as I can't look certain directions without crawling to 5fps, and if bots enter the building, I'll drop down to <1fps. This also used to be the case with ragdolls, but that has since been fixed since CTE.
I've fiddled around with settings a bunch and I've narrowed it down to shadows. I used to be able to run the game with the setting at high with decent performance, but now if I so much as take it up to medium from low, I get an immediate 40% performance decrease, regardless of any other setting. With tesselation, ambient occlusion, post-processing, and shadow resolutions all on/maxed, the FPS decrease is the same as with those settings set to off/minimum. In fact, with shadows set to low, I can push everything else except supersampling to ultra, but as soon as I set the shadows to medium, I can barely run the game with everything else set to minimum.
Frankly, this is really disappointing because I love how good the shaders are, and I find the game very difficult to play without shadows... It just turns into a washed out mess of bloom lights.
As for my rig, I'm running i5 devil's canyon, AMD R9 380x Black, and 64GB of RAM.