[Ham-Computers] Optical Mouse Pointer Cursor Drifts off Screen

[Jim Hill]

I have an unusual problem with my Dell OptiPlex Inspiron.  it's a 2 GHz 
Pentium 4 with Windows XP Home.
A short time after turning on the computer, the mouse cursor drifts off the 
screen. It may be visible at one corner (upper right, usually), but that's 
it. The buttons seem to work, but it's hard to tell.  It's an optical 
mouse, and I tried another optical mouse with the same results.

It's not connected to the Internet, so a virus is not too likely.  No 
antivirus software is installed.  However, I do transfer data with floppies 
and CD-RW's. The other computers have up to date virus protection, but I 
may have checked some old floppies that were used ???.

Any suggestions?
Jim