Shader Bar Filling in most big packs?

My Shader bar seems to be the bottle neck along with my CPU in most fights.
It's constantly a full green bar in large packs/harbingers/delirious maps.

Any way to diagnose why?

Bump. CPU is self explanatory, shader is a bit more mysterious, wiki isn't much help. Talks like it's software but then mentions gpu hardware.

so ok need new cpu, fine, new gpu, also fine, but how do I choose a new card if I want to make sure shader is no longer the issue? Not looking for a good card recommendation, looking for knowledge on how to find said card myself.

Shaders are only the issue if the shaders cache was cleared recently and your cpu/gpu/drive are not fast enough for keep up with the in-game situation during shader generation.

If your shader cache bar is the only one filled up to maximum value and you experiencing shuttering / low fps during combat — the issue is probably a high latency disk drive. You can try to move the shaders cache folder to a faster drive, add the folder path to your security software exclusions list etc.

And just for example, I have moved the cache to RAM Drive that has twice lower latency and three times faster random read speed than my NVMe SSD and yet the Shaders bar is almost always full during juiced combat.
I'd recommend you to not worry about the metrics, the bars are hardly mean anything specific.

It fill up quite often with harbinger and i have not cleared my shadercache (let the game clear it for me)