On Windows 10, type advanced system settings in task bar
click on performance settings
then click on the advanced tab
and you’ll see Virtual Memory
click on Change
Now you can select all your spare SSD’s or just the one and set a custom size
Remove the paging file from the drive/s that holds Windows and UEFN/Fortnite, should speed them up too
You’ll have to Restart PC
The virtual memory is just an extension of RAM, windows and other programs use it as extra ram for lower priority memory storage
Windows by default sets the hard drive to use about 11% of hard drive size, so a full disk will slow up a PC because it reduces the size of the paging file