We are unable to tell if it is a DCS or C1100 by the CS-24 designation. That designation is used for both types.
Unfortunately I don't know how you will enter the BIOS if F2 does not work. We do not have any other variations of the BIOS listed in the documentation. I don't have access to DCS information, and I suspect this is a DCS system. If it is a DCS server then it could be running a custom BIOS. I would suggest contacting the seller for more information on the server.
Thanks