Help on asrock z390 gaming 4

Hi everyone,
I am new to mining,
Just wondering i have asrock z390 gaming 4
Currently single rtx 2070 is attached toit.
Can i get another 3070 place it right under the 2070 for mining?
I googled that this mobo doesnt support SLI cause of pcie x16 and x4 or something?

Any advise? Thanks a million