Monitor Position Adjustment

I am running Windows XP Professional on my Dell 8300 with a Dell E171FPb monitor and a 128 DDR ATI Radeon 9800 card.  I replaced the monitor cable and find that Windows in 1024 X 768 @ 60 HZ resolution (which I have been using with no difficulty previously) is misaligned off the monitor to the right.  The horizontal position adjustment feature on the monitor moves the screen to the left but still leaves Windows misaligned to the right by about an inch - the right side of the Window (where minimize, maximize & close are) is still off the screen to the right and there is a black area about 1 inch wide to the left.  I have a second Dell which has the same manufacturer provided cable as the one I replaced so I tried that and still have the same problem.  Windows is running perfectly at the optimum setting of 1280 X 1024 @ 60 HZ but this setting is a major strain on the eyes  I found how to use the monitors horizontal position adjustment feature in the on-line manual.  I also checked to see if there were any updates to the monitor driver - MS says I am using the latest driver.  I have searched in the Dell Community Forum and at the Windows XP site but I can't seem to find any other information on a hardware or software adjustment to bring windows into alignment at the lower resolution.  Hope I have provided enough information to get help or direction on how I might find a solution.