Mac Mini + Sharp Aquos: Signal is not compatible? HELP

Question

I am trying to get an Intel based mac mini to display on Sharp Aquos LC-45GX6U TV. I am using a dvi-to-dvi cable.
When initially connected, it worked fine, outputting at 1280x768 at 60Herz. It is not the native resolution for that TV, but close enough to display OK. I tried to play around with resolutions and as soon as I switched to another res, the TV showed a black screen with a message "signal is not compatible with this input". The funny thing is that when restarting the mac, it shows the boot screen fine with 1280x768 at 60hz shown in the right top corner of the TV. However, as soon as it boots, it goes back to the black screen with the dreaded message.
I have tried connecting other monitor(s) and TVs (all of which work fine) and then changing the resolution back to 1280x768, then reconnecting to Sharp Aquos. It doesn't work.
I have tried clearing PRAM and NVRAM - it doesn't work. Still gives the same message.
I tried deleting plist files on the mac (which supposedly save monitor settings) - it doesn't work.
I tried booting it in safe mode and it worked worked, if you reboot in normal mode, it goes back to the dreaded messaged. I then tried going back to safe mode and playing with resolution there. Once I did this, it showed the black screen with the message in safe mode and now the safe mode does not work either.
Please help!

Answer 1

Probably the best thing to do at this point will be to trash the preferences file(s) associated with displays. In /Library/Preferences there should be a file labeled com.apple.windowserver.plist. Throw it in the trash. Also, for however many user accounts are on the mini, there should be files in /Users/name/Library/Preferences/ByHost that are named com.apple.windowserver.xxxxxxx.plist where xxxxxx is a hexidecimal string of letters and numbers and where name is the name on the account. Throw all of those files in the trash as well, then restart the mini.
When OS X restarts and finds those files missing from their expected location, it will generate fresh copies with factory default values. That should give you a fresh start with your Aquos. Throwing away the .plist files described will also cause the loss of any custom color calibrations you might have done, or any other display specific preferences that may have been stored.