Blank screen from DVI when leaving PC for long

[madcat]

I use GB-PVR on a T42 laptop, docked in the docking station.
Docking has VGA and DVI out.

Until recently, TV was connected via the VGA out on the docking station, and all worked fine.

Since few days ago, I had to change to use the DVI (through a DVI->HDMI plug, and HDMI cable to the TV).

Ignoring for a second the problems I have that it does not recognize the native TV resolution (which did work on VGA), but the problem is that when I come back to use it after a long time (several hours, say the next day), I see a blank screen on the TV.

It is sending signal, as if there wasn't the TV says "no signal", but TV doesn't complain.

However, it's not a screen saver, cause using the mouse or even keyboard doesnt bring the display back (I can hear the GB-PVR clicks from the sound system).

Only thing works is hitting Fn-F7 (in IBM language, this is cycle between internel/external/both screens). Then TV suddenly shows picture.

In Power Settings, "Switch Off Monitor" is set to Never.

Any idea how to keep this DVI on forever?
Thanks.