If you can't even read the model # on the system, you need to at least post a picture of the thing. There may be model info in the BIOS, running a program like Speccy or CPU-Z will give you some system info, at least the motherboard model which you can then do a search for. Also there may be some text or other files on the system from the OEM setup that contain the model #. Asking whoever gave you the system is an option also I would think.