Fortimail 400 - Replace Hard drive

[#1]

Hi, I think our hard drive on our Fortimail 400 is failing. The device crashes every day and needs to be rebooted. And when i try to delete some rapportes it reboots. Firmware version: v4.0,build0130,100420 (GA Patch 3) I' s there any required specifications on the hard drive i replace it with? Can i use a not partitioned drive with no file system or does it need to be partitioned in a way ? Can see in the product info that the drive must be 1 Tb or less....