turning off screen

[prayner at unimelb.edu.au]

I've recently changed computers and linux version. 
I've been using sudo vbetool dpms off
for years to turn off my screen.
It's no longer working
Looking around the bug reports there's much talk of setting the
selinux boolean mmap_low_allowed 
but this already appears to be set true.
I'm not seeing anything in the audit log when I try to run vbetool now
so I'm at a bit of a loss.
Anyone else seen this recently?
The machine is a DELL E4310 running FC13
thanks in advance
Peter



-- 
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Peter Rayner
room 330 
School of Earth Sciences, University of Melbourne, 3010, Vic, Australia
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mail-to: prayner at unimelb.edu.au