Since League of Legends is an online game, there are servers in the back that provide the computing power for the mass of data that is required to run the game. The maintenance, servicing and operation of these servers is quite complex and sometimes works over long distances.Restart the game and see if the League of Legends frame drop issue is fixed or not. Fix 2. Update the Graphics Card Driver. As you know, League of Legends recommends a DirectX 9.0 or better graphics card. If your graphics card driver is outdated or corrupted, you may also encounter the League frame drops issue.
So run it as an administrator to see if this fixes the slow download issue. Press Ctrl + Shift + Esc key together on your keyboard to open the Task Manager. Find League of Legends program. Right-click on it and click Open file location. In the file, find the LOL Launcher.exe. Right-click on it and click Run as administrator.
If that does not work go to start/computer/OS:C/Riot Games/League of Legends/RADS/Projects and Delete lol_launcher and lol_patcher and then relaunch the game, it should reinstall these two files on launch and that is where most errors occur. If that doesn't work, try doing the same but with the game client and air client in that folder.