T7910 SAS SSD 2.5" Drives max storage - help!

Hi,

I have a little confusion about the max possible storage that I can use in T7910 (the same confusion in the T7810)

I have many 2.5" enterprise grade 12 Gbps drives  (SAS and SSD SAS), with different capacities (from 400G to 8To).

I want to push to the max, but when I read user manual, and from what I understand (see attached), the max will be:

-> 8 x 400G SSD SAS, Or

-> 8x 1.8 To SAS 10k, Or

-> 8x 600G SAS 15k

Is it that?

If I want to use 4 x 2.5" drives (SAS or SSD SAS), what can be the limit?

PS: if the limit is 400G SAS SSD, why they are proposing PX02SMB160 witch is 1.6 To SSD SAS?! https://www.dell.com/support/home/fr-fr/drivers/driversdetails?driverid=2n3cv

Thank you a lot for helping me to fix this misunderstanding.