For starters, are you buying new hardware? Or are you upgrading your existing hardware to Vista? Most of Microsoft's system requirements should very definitely be described as minimum. I mean overly minimum. It's even a little contradictory because the video requirement is more in keeping with advanced newer hardware, and the CPU and memory configuration is more like what you'd expect from an el cheapo PC circa 2004.

Or let us put it another way: This is the salient information you need to know about system requirements if you want to fully enable Windows Vista's Aero user interface:

DirectX 9 (DirectX 10 preferred) 3-D graphics processing unit with a WDDM driver, 128MB graphics memory (minimum), support for "Pixel Shader 2.0," and the ability to display a color depth of 32 bits per pixel.

Although graphics cards that share main system memory are acceptable, you will find that the best approach is 256MB of dedicated video RAM. We have seen some 64MB dedicated video RAM mobile graphics processing units that support Aero nominally, probably because they share main system memory beyond the dedicated 64MB.

The rest of Microsoft's Vista-capable system requirements read like this: