rsp
2
You may have installed v7.x because the v8.x lacks some features.
The v8.7 is pretty fast as well as v7.x.
I think that it is issue with your php.ini file. You need to set some parameters correctly in order to work it well.
Here are few links for you:
https://expertincrm.medium.com/how-to-improve-the-speed-of-sugarcrm-instance-657449fd1ad7