Bulldog 1 wrote in Sat Aug 26, 2017 10:18 am:How can optimize FG? I have the settings at the lowest graphics
There is plenty written about this subject. This is one link with lots of information.
http://wiki.flightgear.org/Troubleshooting_performance_issues
This is on the sidebar of that page and might prove useful.
http://wiki.flightgear.org/Howto:Troubleshooting_Memory_Issues
There is also tons of more specific information in the forums, but you'll have to take some time to search for it.