Extreme Tech gives us some good speculation on how to build a Windows Vista system now. It’s based on the Beta 2 version due out in April, and a lot of surmises on the system requirements. Here’s a taster:

“… it’s likely that the Windows Vista’s feature list is now stable enough that we can predict what kind of system you’ll need to build today to accommodate the new OS. Here are a few details we do know:”

* Vista moves away from GDI/GDI+, Microsoft’s current graphics API used for the Windows desktop. Instead, Microsoft will use a desktop compositing engine built on DirectX. Each window will be its own 3D surface. There will be a fallback mode for systems that can’t handle the 3D load. Note that GDI apps will run, because a GDI layer will exist atop the Desktop Window Manager.
* Windows Vista will ship on DVD discs, so a DVD-ROM drive, at a minimum, is required.
* Microsoft is encouraging hard drive makers to develop hybrid drives. Hybrid drives with a large flash memory cache on board, probably 128MB or larger.
* The Windows scheduler has been improved to take better advantage of dual and future multicore processors.
* Support for HD-DVD will be built into the operating system.
* Versions with Media Center capability will support CableCard for HD playback over Cable TV connections, provided you’re a subscriber.