At my office we have an Apple Server running Xserver which, among other things, we use as network storage.
Previously we had our Graphic Designer setup on a Windows Vista machine, and everything was working great. Recently we upgraded his machine to a faster one running Windows 7- unfortunately it has caused performance problems when it comes to using the network storage. Both machines are connected to the Apple Server via Gigabit Ethernet connections.
Essentially the issue is that, while browsing our catalogue of images the Windows 7 machine takes an unreasonably long amount of time to generate thumbnail previews of the images, the Windows Vista machine had/still has no issue rapidly producing thumbnail previews when viewing the same network folder.