19 boot problem: shim ?

[Robert M. Albrecht]

Hi,

I installed F19 on my Linux machine, running several Fedora-releases 
without problems.

But F19 does not boot at all. Installation (USB, Live-CD, Install-DVD 
and pxe all tried) produces no error messages or warnings. At least I 
can't find them.

The system reboots after installation and nothing happens. BIOS passes 
and Grub should show up but, but doesn't. Switchin on/off UEFI does not 
seem to have any effect.

Of course shim comes into mind. But how to debug Shim ? Any magic keys 
to produce a log or something similar ? Can shim be deactived in F19 ?

cu romal