auto wallpaper changer

I have a DEll 30" monitor and Windows Vista home basic and a GeForce
9600GT graphics card.

I have always used Auto Wallpaper Changer by Steve Murphy and found the
programme reliable and excellent.

With the monitor set to 1024X768 the wallpaper images are displayed
full screen.

However it the monitor is set to 1920X1200 the wallpaper image is
reduced to about 1/4 full screen size.

Manually selecting the same picture in Vista "change Wallpaper" at
1920X1200 displays the image full screen no problems.

Can anyone suggest a fix or another wallpaper changer which may handle
full screen images at the 1920X1200 level


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gerryr1gerry