Are you using a vertical mount then for you GPU
I have the same case I just chucked 3x 120mm fans on the bottom of my case as intakes I did turn the rear exhaust fan around so it to was an intake for positive pressure in the case I found it help with temps alot both GPU and ram temps dropped by 3~4 degrees
Horizontal mount, with no bottom fans.
Thanks for the tip but, I'm very much against fans on the bottom of the case, dust and extra noise, yes I know those fans can get rid of the trapped hot air in between side panel and GPU but,
that shouldn't exist in a XL case with marketing for good cooling in the first place. The fault is in the PSU chamber pushing MBO too much towards side panel while the width of the case becomes mediocre. I really don't care if they rectified that on EVO cause they added a 50-60£ premium. Looks like they pushed ppl into buying their expensive Riser cables brackets.
Vertical mount for me is a no, I need the rest of my motherboard usable. Also vertical mount might bring GPU fans too lose to the side panel.
I cut the case grill of the rear fan and that dropped my GPU temps with 5-7 C, those grills if we are lucky, have at least 46-48 % gaps, which we can agree is very bad for airflow.
Now GN has some experimental tests
Porosity of the Grills, however are other test like the one made by Puget Systems in 2011 showing how grills are hindering airflow and add noise.
Lian Li has no excuse in adding such grills in 2022 for an expensive case with cooling in mind.