Entropy

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There are a lot of reasons to run a slim Windows install; using less space because you only need the essentials for VMWare Fusion as LifeHacker suggests - perhaps performance reasons. But either way, LifeHacker has a great guide on doing it with nLite; GameXP and more.

That means that the virtual machine will run more quickly and take up fewer resources on my Mac.

On the other hand, a lightweight Windows install is also perfect for older hardware that just can’t keep up with XP. In fact, your hardware doesn’t even have to be that bad to still enjoy benefits of this process. A slimmed down Windows install is also appealing for the performance gains it affords, because it allows your computer to allocate more memory and resources to individual programs rather than the operating system as a whole.

Read more at LifeHacker.