Cant get full resolution on external monitor

[David M]

I have win XP home on a Dell Inspiron laptop. The problem is that I cannot get full screen resolution of 1200x1600 on my external dell 20" lcd.

It used to be that I could hit fn-F8 and the screen on my monitor would turn off and my external 20 inch monitor would automatically go up to 1200x1600 when the laptops screen turns off.

I tried control panel/display/settings ..slid the bar over to 1200x1600 and apply.....no luck

Seems the only way to make this work is to turn the laptop screen off....but fn-F8 no longer works.

Any ideas?

Thanks

[David M]

Hitting fn-f8 no longer does anything...something changed...gradually...sometimes it would work and sometimes not..and now it does not change at all.

[David M]

What if I uninstalled the drivers on my laptop monitor so it would not come on so I could get full resolution on my external monitor?

[ktkendall]

Have U looked into the BIOS settings? Sounds like they may have reverted back to default.. I know my old laptop settings to control the display like you are talking about were found in the BIOS....