I think this is an OS problem but we'll see what the consensus is. It's a little hard to describe accurately. I reformatted my HDD recently and first noticed this anomaly when I engaged the "STARFIELD" screen saver in XP. If you've seen it you know that the point of origin of the "STARS" is suppose to be in the center of the screen. On my screen the point of origin is almost off the screen to the right. Also, the cursor is suppose to stop at the edges of the screen. On mine it does on 3 edges but not on the right side. I have done some experiments and it appears that I can move the cursor approximately one full screen width past the right edge. Everything else seems normal. Wallpaper and programs fit normally. I probably wouldn't care except it's very annoying to constantly lose the cursor off the right side of the screen and have to relocate it. I've already exhausted all the driver variables and also tried every adjustment on the monitor itself. Any suggestions welcome. Thanks in advance.
There was a setting which allowed you to have a much larger desktop than your monitor was capable of displaying... the desktop generally scrolls when it is set larger than the resolution. I do not remember where this setting is located, and I can not find it in Vista, but I know it exists... as I've played around with it before. It may not be called "desktop size"... and I certainly don't recall what it is called, because it's been so long since I've seen it.
It also wouldn't hurt to check if "Extend my desktop onto this monitor" isn't checked for the 2nd display.
I have two monitors. My left side desktop was larger than the monitor, and whenever I moved the pointer to the edge, the entire desktop image would scroll.
After reading the comments on this thread, I decided to look at it as a flaw in XP. Then I reviewed the settings for the desktop and noticed that my two sides were set for two different graphics cards. So I tried picking the alternate graphics card for the left side, and the problem went away.