Hello,
Thank you for posting in Microsoft Community forum.
Based on the description, I understand your question is related to your computer is not experiencing any performance issues while playing games, even though your RAM usage is not going over 50%. This is not necessarily a problem, as long as your computer is running smoothly and not experiencing any lag or crashes.
Regarding the stuttering issue you mentioned when using Opera GX while playing games, it could be related to the amount of RAM being used by both applications simultaneously. You may want to try closing other applications while playing games to see if that helps with the stuttering.
As for the excessive amount of mapped RAM on standby, this means that some of your RAM is being used to store data that is not currently being actively used by any application. This is normal behavior for Windows, as it tries to optimize the use of available resources. However, if you notice that your computer is running slow or experiencing performance issues, you may want to consider upgrading your RAM to increase the amount of available memory.
I hope this information helps. Let me know if you have any further questions or concerns.
Have a nice day.
Best Regards,
Molly