It can be closed. I got referred to the solution to my question , located at page 126/127 of the T7820 manual
Hello, I have a T7820 with 2 bays converted to sas/nvme for pci-e ssds, and 2 bays for the classic sata hdds. Today I put inside 2 x 4TB sata hdds ( the 7820 doesn't have any additional controller, so it's just sata from the mb ) and I sort of expected to see  what I can see for the nvme ssd ( the status led, and the activity led being lit ). But the 2 leds are off, in both sata bays ( I do get the activity light from the small led just under the power button ). Is that as it should be and the caddy leds should be working only if using a sas ( with a controller ) ? Or is there a way for me to have the leds working in the 2 caddies, with the 2 exos sata drives ? Thanks
Question about the flexbay status lights of the sata caddies in a 7820