Microsoft says Windows 7 requires at least a 1 GHz single-core CPU, 1GB of RAM, and a 16GB hard drive. Vista's minimum specs: 800 MHz single-core CPU, 512MB RAM and 20 GB hard drive.
To run Vista's "premium" features, Microsoft said users needed a 1 GHz single-core CPU, 1GB of RAM and 40GB of hard disk space.
Microsoft has not given guidance on what is needed to run Windows 7's premium features. So Softchoice, a close Microsoft partner, created its own: 1.6 GHz single-core CPU, 2GB of RAM and 32GB of hard disk space.
Of the 12% of PCs that failed to meet Windows 7's minimum specs, all required both a RAM and hard drive upgrade. To meet Windows 7's premium specs, 35% of PCs needed more RAM while 21% needed a bigger hard drive.
Memory and hard drives are cheap, and the upgrades can be done simultaneously with Windows 7's installation, minimizing IT labor time, Williams says.
So does that mean companies should keep their existing hardware and do the in-place upgrade to Windows 7? Not necessarily, says Williams, who notes that Softchoice's research shows support costs "tend to escalate" for PCs past the 42 month mark, making it financially wiser to buy new hardware at that point.
Williams also acknowledged that Softchoice did not factor in the PCs' graphical capabilities, provided in laptops and business PCs via non-upgradeable GPUs built into the motherboard. Those GPUs are less powerful than consumer add-in graphic cards, meaning they may not be powerful enough to run Windows 7's premium Aero graphical features without some lag or delay, he said.