HP C240 Visualize: power up screen standby

[Kristof Loots <kristof.loots@skynet.be>]

Hi all,

I am trying to install debian on my HP C240, but I am even not up to install.  When I power up my machine, my screen remains in standby.

I recall when booting, a message saying "press TAB to change screen" appears.  When I press TAB several times my screen turns on and it says " Out of frequency".

Is there a way that I can boot with a lower frequency?  
Or does someone know  the sequence of changing the settings when pressing TAB?


Kind Regards,

Kristof