I have a DGM monitor and got the same problem - had to boot up in vga mode to see anything since it kept on saying display out of range and then going into power save mode. I did a long useless trawl on google to find DGM website but to no avail. Finally I found some articles that suggested turning off the monitor by its own switch and powering off the plug, switch on the computer, wait for it to complete the boot then turn on the plug and then the monitor switch. This didnt work for me but the article writer was pretty convincing so I thought Id add it too. Now for my solution, this is going to make you smile. Basically all I had to do is reinstall the video drivers from scratch. I have a nvidia card and nothing I did would fix this apparent "refresh" problem until I booted in vga mode from XP by pressing F8 constantly from bootup and choosing the vga option. Once loaded, browse to your pre-downloaded nvidia or graphics card install file and re-install over the existing driver. This reset something and hey presto everything works fine now. just as a side note, i disconnected my monitor to use its cvable on anotehr monitor and when i reconnected it I had the same problem. Another reinstlal of the video card drivers solved the problem again. Hope this helps someone else out there!
Dean Mitchener, June 2009