Use these guys OS its very well made http://download.ltcrabbit.com/SMOS-LTCRabbit-Edition-V2.zip
here is moar info how https://www.ltcrabbit.com/index.php?page=os

These cards are not repeate NOT 280X, they are cheap GPUs with modified BIOS in order to show certain stats in windows. It can be easily proved by re-flashing the bios or just run CGminer on them and you will see exactly what they are capable of if even get recognized by the system.