Can you update BIOS and iDRAC to latest FW on the server and check whether behavior exist. You can also try with another keyboard / connect keyboard to USB slot on back side of the server and check the behavior. If you have access to iDRAC Virtual Console can you check whether keyboard through virtual console us working when system is in BIOS. 
Hi All, Hope you all doing well. Please to know that i had a new 4 PowerEdge R640 servers, the issue is with 2 servers, when i plug the RGB keyboard and try to choose F2  to enter the bios it dosen't work(same for other keys) but after the os boot wich is a microsoft windows server 2019 the keyboard work. All Servers are the same version of bios. But for the rest of 2 servers the keyboard is functioning also i try with rebooting the server but with no luck. Looking forwards for you help and thank in advance.   Regards,Franks
Keyboard dosent work with R640 why?