We have installed several machines running Windows Vista at a client site. These machines run the same set of applications each day and are not operated with by any user. They mainly run a 3D application for digital signage purposes.

After a few months I noticed that several machines suffer from really bad stuttering. The performance is unacceptable.

At first I figured it was faulty hardware. But after putting a fresh image on them, they run perfectly fine again.

These are Core i7 machines with GTX 280 graphics adapters. They should be able to handle the workload without any trouble (and they do, at least for a while).

I really have no idea how to track down the source of this issue. Especially since not all of the machines display the same issue.