Find Spare Parts is a side quest in Fallout: Brotherhood of Steel, and can be initiated within the Secret Vault's gardens.
Ching Tsun needs computer parts for the Secret Vault, and requests for the Initiate's aid. With access to the outside world, this task is about as simple as they come.
The computer parts needed, can be looted from many of the robots inside of the Secret Vault itself, even before the quest is given. Afterwards, and upon handing the parts over, Ching Tsun will reward the Initiate with 200 caps, as well as 100 XP for each part.