I've got three machines on my desk right now, not one of them is from what you would call a traditional supplier of PC equipment, and yet each one is capable of running an amazing range of operating systems, including those from major competitors.

Case in point, two of the machines are from Apple (a Mac Book Pro and an iMac). They are capable of running OS X, Windows, Solaris and Linux.

Also on the desk is a Sun Ultra 20M2 that I have on test at the moment (see Ultra 20M2 Arrived). That runs Solaris, Windows and Linux.