Now I am sitting on the portable (C2D) and just did a simple test.

1: move the mouse from side to side on the screen with no other applications running. No problem of course.
2: Started one compilation in visual studio, and moved the mouse from side to side on the screen. Now the mouse starts to “disappear”. The mouse pointer freezes and shows up in another place, you need to look for the mouse pointer where it is. It doesn't happen that often but it happens.
3: Started two compilations the behavior is now much more common.