Well why not? Aplying the right config changes.....
But you can buy a HBA like dell H200 and plug in 8 drives. I'm no expert, but there are plenty of HBA, even for more drives, and with port multipliers the amount of hard drives you can connect grows.
For example, Petabytes on a budget: How to build cheap cloud storage, they use only 4 sata cards and 9 multipliers to connect 45 drives