Common Java Client Performance Issues
Game Versions: These steps are for the Java client.
Performance issues with the Java client could be caused by a number of things please read this article to find out how to resolve them.
If your game crashes and you receive no error message or "Error_Game_Crash", then the problem could be caused by corrupted files in your Jagex Cache. Try clearing your JAVA Client cache files.
Client performance issues - Stuttering and running slowly
If you find that you are experiencing stuttering, or RuneScape is running slowly, then you may find that allocating additional memory to the client helps improve stability.
This solution won't resolve Lag or FPS Issues.
Interface Sizing - Windows 10
On Windows 10, if you are using a high resolution screen, you may find that certain things (the login screen and the interfaces in-game) are scaled down. This is caused by a Windows 10 update check out how to fix the scaling issue.
Check out Java Client Install issues if you're having problems installing the Java Client.
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