I happened to notice in task manager that there is an ATIECLXX.EXE process with a create date of 11/24/09 running. I tracked it to the service listed in the title.
Previously, there was a 4890 in the system, along with a version of the OpenCL SDK. Everything was un-installed. Is this something that just failed to be cleaned up? The service has no description. I disabled it, but TaskManager does not expose user interface to actually remove it.
There is a second version of this file in a Windows/System32/DriverStore/FileRepository directory, which led me to think it was the display driver, but there are also parts of CAL there to make me less sure. Please clean up where appropriate.