Back in the late 90's I learned that when installing XP it would pick one of two sets of libraries, one set for single processor machines, one for SMP installs. The difference was the SMP version had extra code to handle multiple processors. The drawback was the SMP code was a bit slower, which is why the single processor version exited. There where steps somewhere to convert a single processor install into a SMP install. I have a Windows 7 virtual machine which was installed as a single processor machine that I would now like to run as a SMP VM. Q: Are there two different flavors of Windows 7, both a single processor and a SMP version? Q: If there are, how does one convert from one to the other?

win7 should check on booting what hal it needs. if it should fail (seen that when using a vpc vm lateron within hyperv while not have had the integration services deinstalled in time), you can adjust manually in msconfig -> boot -> advanced -> number of cpu's