HP Proliant DL120 with 3rd party 4Tb drives not showing full capacity

We've purchased a HP Proliant DL120 G7, which has an onboard Smart Array B110i controller. In the server, we've bought 4 x Hitachi 4Tb SATA drives, mounted them in HP drive caddies and installed them in the server. However, the B110i controller only shows the drives as 1.8Tb:

If we disable the B110i and use the AHCI controller instead, all 4Tb per drive is available. We'd really like to use the B110i if possible; does anyone know why the full drive capacity isn't available? According to the QuickSpecs, 4Tb drives are supported (and yes, I realise these aren't HP drives).

I swear, when I read questions like this, I wonder why people are even using 4TB disks in inexpensive servers with low-end controllers. Do you really need 8TB-12TB usable in a four disk setup? What are you storing?!?

Either way, the Smart Array B110i controller is not compatible with drives larger than 2TB in RAID. It's not well-documented or noted online, but you've run into a product limitation. Remember, this controller predates the introduction of 4TB disks by a bit.

If you need to use those specific 3rd party disks, then you're going to have to swap controllers or use software RAID.