4Game

I couldn't find much information when Googling about this issue. Just want to put it out there more clearly, so hopefully this helps some lad. This issue happens when you change your GPU and your old drivers are still present.

To remedy this;

1. Download and extract Display Driver Uninstaller (DDU)
2. Download your driver from the respective website
3. Boot into safe mode (Must do this, if you know how, skip to 7)
4. Open Start Menu (press home button), search "Advanced Startup" and press enter. It will open the settings app. Click "Restart Now" under Advanced Startup.
5. Once your PC reboots, click Troubleshoot -> Advanced Options -> Startup Settings -> Restart
6. PC will restart again, press the number that corresponds to "Enable Safe Mode". Usually its 4 but could be different if you are using a different version of Windows.-
7. Open DDU, click options. Make sure everything under Nvidia, AMD and Intel is selected/marked EXCLUDING "Keep NVIDIA Control Panel". All the things your GPU needs will be provided by the driver. Close the settings menu.
8. Press "Clean and Restart". Once your PC boots up, your resolution will be set at the lowest as your drivers arent installed. Open File Explorer and install your driver. Restart your PC once more.

I recommend you download your driver before doing the DDU thing because using the browser at 800×600 resolution is not fun. If your game still lags when shooting after doing these steps (and if you have recently changed your GPU), you might have missed a step or did something wrong.