Found out that my hp Z800 workstation as well as the new Z820 workstations do not support larger than 3tb internal 7200rpm hard drives. i now have to go return my two 4tb drives i bought and was extremely excited about and replace with 3tb. fyi. there is no loophole that i am aware of.

Wd 4tb drives not supported by hp workstations

HDKnows April 10, 2014, 12:55pm 2

Hello,

Thank you for sharing this information. Hope it helps any other user with hp Z800 and Z820.