When creating a task sequence to deploy an operating system. It’s possible to ask for a computername when running the task sequence on a unknown computer, for instance a new computer.
Right click on the collection: All Unknown Computers and select: Modify Collection Settings.
Go to tab: Collection Variables click on the new variable icon. Give the variable the name: OSDcomputerName and leave the value empty.
When booting the task sequence, on a new computer (or remove the computer first in sccm) the following screens will appear:
When the following screen appears, double click on the variable and give the right computername for the new computer.