Since the anti-trust actions forced Microsoft to allow OEMs choice, Dell has been offering a lot of Linux for their systems, so that would be eating their own dog food too. OTOH, their Windows is obviously working well enough, and as the "shining star" of Windows installations, I'm sure they get a great licencing deal from Microsoft.
Yea I know I bout a couple of PE 1700's running Linux for some web app clustering. What I have found is dells support of the redhat boxes is a joke. I mean to say they make most of their money selling windows servers so in that way they are eating thier own dog food..