C71 is TERA2321 chipset and C75 is E3869M6.
No, they have their own specified firmware in the chipset, force wipe firmware out will lead them to be malfunctioned.
C71 is a specialized zero client for PCoIP solution, through which user can achieve unified management of high-end graphics workstation designed to render 3D graphics solution over Teradici PCoIP Host.
C75 is a specialized solution for accessing Window multipoint ServerTM; Userful MultiSeat TMLinux and Monitors Anywhere; C75 presents server desktop and applications to users once it is powered on and connected to the server.
Zero clients are gaining ground in the VDI market. These are client devices that require no configuration and have nothing stored on them. Zero clients often require less setup than a thin client. The deployment time can be lower provided those carrying out the deployment have properly set their environment up. 
Thin clients and other slimmed-down devices rely on a network connection to a central server for full computing and don’t do much processing on the hardware itself. Best thin and zero client product choices for your VDI environment really rests within the software embedded on the clients.
Centerm C71 and C75 are in the fields of Zero client.

Zero client is a server-based computing model in which the end user has no local software and very little hardware; zero client can be contrasted with a thin client which retains the operating system and each devices’ specific configuration settings in flash memory.