It's Still Early
As we continue to develop Vista-ready benchmarks and to test as many systems with Vista preinstalled as we can get our hands on, we'll update you with additional findings.
In the meantime, if you are contemplating an upgrade, our preliminary tests suggest that Vista will be a decent performer on any machine with dedicated graphics hardware.
Looking back at our value-PC charts, most systems from two years ago--$1000 models carrying Pentium 4 processors of around 3 GHz or Athlon XP CPUs of around 2 GHz--would do just fine as Vista machines after a simple RAM boost. And dual-core desktop PCs appear to be great candidates for Vista upgrades.