Windows Experience Index
After you install Windows Vista, the operating system will measure the performance of the four main hardware components of your PC – CPU, RAM, VGA and HDD – and will assign a performance index for each component. For the VGA, Windows Vista assigns two scores, one for Windows Aero and another for gaming. The lowest of these five scores will be called “Windows Experience Index”. You can see this index by clicking on System on Control Panel (pressing Windows Pause/Break keys is a shortcut to this option), see Figure 5. If you want to see all five scores, click on Performance Information and Tools icon on Control Panel (see Figure 6).
Whenever you make hardware changes to your PC, you will have to update these indexes, by clicking “Update my score” option (see Figure 6) or the “Refresh Now” button that will appear when Windows detects that there were changes on your PC hardware – this update isn’t done automatically by Windows.
The problem is that even very high-end PCs get a low score here. To test Windows Vista we built a PC using a Core 2 Extreme QX6700 (a quad-core CPU running at 2.66 GHz), 2 GB DDR2-1066 RAM from Corsair, ASUS P5B motherboard (Intel P965 chipset), GeForce 7950 GX2 from XFX (which is factory-overclocked), Maxtor Diamond 9 Plus hard disk drive (40 GB, ATA/133) and Zalman ZM-600HP power supply. With this configuration the maximum score we got was 5.9! From the above list you see clearly that our hard disk drive was quite outdated, being the component that achieved the lowest score there.
Installing our GeForce 6200 TurboCache 64 MB 64-bit on this PC we achieved a 3.5 score for Windows Aero and it wasn’t the end of the world, like we mentioned.
So don’t be frustrated if you get a low score here. This is normal to happen even if you use high-end parts on your PC.