I have a win7 boxee box running 2.6Ghz P4 and 1gb RAM, and 512Mb GFX card outputting to HDMI.
Boxee runs 1080, 720 and SD local content extremely well (local content is actually a NAS).
The only problem I am having is that streaming content from the web is juddering pretty badly so much so as to make it unwatchable.
Any tips would be greatly appreciated.