Cool GTX
Is the KB plugged directly into the MB?  (RE your other thread )
 
Is fast boot off in BIOS?
 
Have you loaded the firmware update yet ?
 
try a USB 2.0 port

Thanks. All good points:
 
No, it is plugged into the KVM. But with another computer, also connected to the KVM, DEL seems to work fine at boot. This would seem to point to the one computer. But this computer works fine with my old Logitech USB keyboard plugged into the KVM. And it works fine with the Logitech plugged in w/out keyboard. So that is why I wonder about the new Z12.
 
Fast boot is not enabled.
 
When you speak of firmware, are you talking about the Z12? If so, after I installed the Z12, I downloaded the latest version of Unleash RGB - v. 1.0.19. In the setup, I checked for firmware - v. 0.25 - and checked for firmware needing update. There was none. Looking right now, I see that RGB has an update to v 1.0.20. I will check into that. I wonder if there is a change log somewhere... Edit: I found it on this forum. Excellent. But in looking at the comments from woewrecker there, I hesitate. He mentions rolling back drivers. Is there some way to do this? If so, I would be more willing to try being an early adopter.
 
The USB ports involved here are all 2, not 3.
 
Thanks