Vista Hardware requirements
According to Microsoft, computers capable of running Windows Vista are classified as Vista Capable and Vista Premium Ready. A Vista Capable or equivalent PC needs to have at minimum an 800 MHz processor, 512 MB RAM and a DirectX 9
class graphics card. A computer that meets these requirements will be capable of running all editions of Windows Vista although some of the special features and high end graphics options may require additional or more advanced hardware. A Vista Premium Ready PC will take advantage of Vista's "high-end" features but will need at least a 1.0 GHz processor, 1 GB main memory, and an Aero-compatible graphics card with at least 128 MB graphics memory and supporting the new Windows Display Driver Model.
The company also offers Windows Vista Upgrade Advisor from its Web site to determine the ability of a PC to run Vista in its various guises. The utility runs on Windows XP and Windows Vista.
Microsoft lists some Vista capable hardware on their web site. The "Vista Premium Ready" laptops they specify have Intel Core 2 Duo T5500 or above CPUs and 1 GB memory.
Windows Vista's "Basic" and "Classic" interfaces will work with virtually any graphics hardware that supports Windows XP or 2000;
accordingly, most discussion around Vista's graphics requirements centers on those for the Windows Aero interface. As of Windows Vista Beta 2, the NVIDIA GeForce FX family and later, the ATI Radeon 9500 and later, Intel's GMA 950 integrated graphics, and a handful of VIA chipsets and S3 Graphics discrete chips are supported. Though some XGI Technology Volari chips were DirectX 9 (including the Volari V3XT which was available in PCI cards), with XGI's exit from the graphics card business it appears none of its chips are supported as of Vista Beta 2.