Workbench 3.1 graphical icon rendering issue

[dschallock]

I am getting some very specific vertical banding/artifacting of icons on workbench with a fresh install of of OS 3.1 on an A3000 with a warpengine 3040 16megs of RAM and 2 of Chip. It does NOT happen all the time, but it will happen once a session and when it does, it doesn't matter how I resize or refresh the screen the problem persists. But I might launch a program and then quit and come back to workbench and the artifacting is gone. There is no disturbance of the icons horzontally. I have not seen any garbage on any other program.. just icons on workbench.

Last year I was getting the garbled graphics on games after the system heated up some and I ended up ordering and replacing the CIA chips with the new cooler running ones. The garbled graphics in games went away immediately. I have been running a 3.9 system through a picasso IV promoted workbench and only recently created another bootable drive with a fresh 3.1 installation on it. I am NOT using the picasso IV for this 3.1 system. Just pure Amiga flicker fixed output from the A3000.

Any thoughts as to what this vertical garbled icons might be caused by?
Thanks!
-Dan