Pilot error. There's a checkbox in the Virtual console configuration of idrac interface that turns on/off video output on the physical connection. Idrac settings are preserved through bios reset.  
Hi All, After updating R810 BIOS to 2.11 I face strange problem with embedded graphics on several servers.  After cold boot it does show "Dell" screen while configuring memory, after that it goes dark. server itself works fine I have access through idrac, no errors reported, built in diag software shows no problem, all memory/cpu tests pass   I tried to reflash bios / reset idrac and bios / turn it off (unplug all cables + hold power for 30 sec), changing VGA cables and monitors  but nothing seems to help. Out for 3 servers I updated 2 had issues. embedded graphics worked fine before update. I also notice that sometimes the first boot flash screen is clipped, it almost looks like the incorrect (unsupported ?)  video mode is selected. Anything else I could try ?  
R810 problem with embedded graphics after BIOS update