Cant get 1024x600 or 1024x576 resolution on Inspiron 1011 netbook

Am wondering if anyone has had this same problem. 

This netbook has been working fine until last night.  All of a sudden the laptop started to go slow, and the screen seems to have grown in height losing the XP task bar at the bottom of the screen.  Going into the display properties, I can only select 800x600 or 1024x768 resolution.  The device manager reports the display as 3 items.  (1) Default Monitor, and 2 instances of Digital Flat Panel (1024x768).  I have even tried up upgrade the driver on the display to Plug and Play Monitor, but no good.

The display adapter in device manager lists two instances of Mobile Intel(R) 945 Express Chipset Family.

I have tried plugging another external monitor into the netbook and everything displays OK on that external monitor.  cycling between the Blue Fn key & F1 which selects external/internal monitor still doesnt make any difference.

I have updated the video driver from the original Resource CD and still no good.

Even on 800x600, I still do not get the XP task bar on the netbook screen.

Looking at the original specification on the netbook, I see that the resolution should be 1024x576 or 1024x600.

I am thinking that maybe this is a hardware fault now.

Any assistance would be welcome.

Many thanks - Chris Brennan