A fairly common consideration in larger organizations re: Encrypting Windows Servers is that often these servers are located in remote or locked-down Server Rooms:
Assuming a desire for greatest-possible security, how does one log into a device at pre-boot that may be located in another building?
Often, these servers would only be managed remotely (i.e. Normally, no local staff would have physical access to the servers). Once into WIndows, of course one can use Remote Desktop to access them. However, auditors and top management might be uneasy with the idea of permanent AutoBoot, and that these servers could boot straight through to an "open" state following a power failure or other outage. because if these servers were compromised (e.g. Stolen) they should stop at Boot Logon and deny access to anyone who did not have the necessary authentication.
Solution/Recommendation:
One option could be to incorporate a KVM over IP device. This type of device permits transmission of Keyboard, Video, Mouse data over IP from the administrator's desktop to the server located in the server room.