(just saving here the comment from JDK-8149371)

Sorry, that's most probably the duplicate for JDK-8069348, but it is reproducible with disabled d3d option (-Dsun.java2d.d3d=false) as well as JDK-8148484, so filing it separately (just in case)

Win 7 + JDK9b101

Please run MultiResolutionIconTest.java from JDK-8149371 with options
-Dsun.java2d.d3d=false -Dsun.java2d.uiScale=2
and move one of the windows over the other. Line artifacts will occur (please see the screenshot attached); the same for sun.java2d.d3d=true.

Cannot see artifacts for -Dsun.java2d.opengl=true