Mac Pro w/ File Vault 2 has no video on restart—must log in blind
My 2013 D700 Mac Pro is running El Capitan, and I just enabled File Vault 2. It took a few hours but completed the conversion just fine. (I do NOT have the often-reported problem of a progress bar pausing when trying to log in.)
Now, when I restart the Mac, I hear the normal boot chime but the display never turns on. (I've tried 2 different displays: HDMI 1280p projector and 4k Dell Thunderbolt display.)
After a long while, the power button light goes out. I press it—just once, not a force-shutdown—and the display comes on. But I have to wait many minutes for the light to go out before I can do that. When setting up a projector presentation before a group, this is unworkable.
During this time before the power light goes out, there are no signs of life: I can't get volume-key clicks, nor caps-lock light. Apple Bluetooth keyboard. (But the port labels do light up if I nudge the machine.) And even AFTER hitting power to get the video back, caps-lock won't light up until after login—but during login the caps-lock icon appears on screen to show that the key, although unlit, is functioning.
What I've discovered, though, is that until the light goes out (presumably a timed auto-sleep), the computer IS invisibly booted, awake and ready to log in. If I wait just the right amount of time (impossible to judge accurately) for booting to finish, then blind-type the first letter of my username, press Return, type my password, and press Return, I can log in. THEN the display comes on, the volume clicks start to work, and the caps-lock light starts to respond. This is quicker than waiting for the auto-sleep, but tricky to pull off.
Therfore, it seems that with File Vault 2, there is no video until AFTER login has completed, OR after the computer eventually goes to sleep on the login screen and is re-awakened.
(Also, the same thing happened, for the first time ever, when the machine first rebooted to BEGIN File Vault conversion. The screen went dark and nothing ever happened, the power light went out—but I later woke the machine, logged in, and then conversion began and went fine.)
How might I try to fix this?
TIA!