Game lagging after Windows 10 20H2 update

You titled your thread about the lag, and referred to it twice in the thread. So I gave you steps for lag.

Now you're saying it isn't the lag, it's the frame rate. So let's try again:

See fixes to speed up games FPS in Windows 10:
https://www.digitaltrends.com/computing/how-to-...
https://www.makeuseof.com/tag/optimize-windows-...
https://windowsreport.com/increase-fps-windows-... (Avoid ad links which intrude into editorial copy, especially avoid Restoro ad)
http://blog.logicalincrements.com/2014/06/frame...
https://windowsreport.com/low-fps-pc-fix/ (Avoid ad links which intrude into editorial copy, especially avoid Restoro and Reimage ads)
https://www.businessinsider.com/how-to-increase...
https://www.thewindowsclub.com/game-stuttering-...
https://www.quora.com/What-computer-parts-incre...

https://www.youtube.com/watch?v=Dj9syk_ApcA

Make sure you are signed into the game and MS Store at top right corner Profile icon. This saves Store games progress.

Do you know when this started? If so See if you can System Restore to a point before the problem began following this guide: https://www.windowscentral.com/how-use-system-r...

System Restore is your first line of defense and can take you back to a point before a problem began. If it doesn't help then you can undo it. Read about it first in the tutorial above and then try restoring to just before this started.

If the problem repeats or System Restore doesn't work then check which Windows Updates were installed at Settings > Update & Security > Windows Updates > Update History, uninstall them there or System Restore again, then immediately check for and block the Updates with the Hide Updates tool explained here:
https://www.tenforums.com/tutorials/8280-hide-s...

Even if you've already tried one of these steps, please do them over in sequence:

1) Check for game Updates in MS Store Hub (three dots at top right of Store app) > Downloads & Updates.

2) Run the MS Store apps troubleshooter at Settings > Update & Security > Troubleshoot.

3) Try to Reset or Repair the game in Windows Settings > Apps > Apps & Features > [Name of game] > Advanced Options > Reset or Repair. Restart PC.

4) If that's not enough then uninstall the game from the same place, restart PC, reinstall the game from MS Store Hub (three dots at top right of Store app) > My Library.

5) If the above steps don't help then go over this checklist to make sure the install is set up correctly, optimized for best performance, and any needed repairs get done:
http://answers.microsoft.com/en-us/windows/wiki...

Start with Step 4 to turn off Startup freeloaders which can conflict and cause issues, then Step 7 to check for infection the most thorough way, then step 10 to check for damaged System Files, and also Step 16 to test a new Local Admin account. Then continue with the other steps to go over your install most thoroughly.

6) Update your drivers and BIOS/UEFI firmware from PC or motherboard maker's Support Downloads web page, using the full model number, Serial Number or Dell Service Tag on sticker. Compare the latest drivers available for download with the ones presently installed in Device Manager reached by right clicking the Start button. Make sure you have the latest BIOS or UEFI firmware, Chipset, Display (Video), Sound, USB3, Bluetooth, Network and all other drivers, or else download and install the latest now.

Updating drivers from the Device Manager or Windows Update is rarely enough. The most basic thing we need to learn to maintain a PC is keep the latest manufacturer's drivers installed from their Support Downloads web page.

7) If nothing else works then do a Repair Install, by installing Media Creation Tool, open tool and choose to Upgrade Now. This reinstalls Windows while keeping files, programs and most settings in place, is the most stable method to advance to the latest version, and solves most problems. https://www.microsoft.com/en-US/software-downlo...

I hope this helps. Feel free to ask back any questions and keep me posted. If you'll wait to rate whether my post resolved your problem, I will keep working with you until it's resolved.

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