Question Low FPS on brand new PC only in League of Legends and its client

Sep 13, 2020
Hey everyone,

I built my first PC yesterday, got Windows 10, all the drivers I need, etc. Tried running Planetside 2 and MB Bannerlord so far and they work fantastic, getting >120 fps on all ultra/high settings in both games. However, whenever I play League of Legends... this isn't the case. First off, the League Client is extreeeemely laggy and choppy, and when I actually start a match I float at around 30-60 fps, but for the first 5 seconds of the game it shows >100 fps. My frames also get progressively worse as the match goes on. I've tried adding the client and the game to my Nvidia control panel because they initially weren't there, but nothing helps. Also tried capping fps at 60, uncapping fps, fullscreen mode, disabling fullscreen optimizations, power plan set to ultimate performance, booted into XMP mode, set priority to high, but nothing changes. CPU/GPU aren't hitting above 75 C in any game... Honestly don't understand why the simplest game is running like I downgraded to a potato. Any help is appreciated. Thank you.

CPU at <10%, GPU at 0-5%, RAM at ~50% during a match.

RTX 2060 Super
1 TB M.2 Intel SSD
16 GB DDR4 RGB Corsair Vengeance (2x8, in the correct slots)
550W Seasonic 80+ PSU
MPG Z490 MSI Mobo
Noctua NH-u14 Cooler

Also, no FPS changes no matter the quality settings (Low-High) or the resolution I choose.