Is Windows Vista slower than Windows XP?

Guardian News Service: "The 'Wow' starts now," said Microsoft when Windows Vista was launched. For some users it was, "Wow, how can this computer be so slow?" But is Vista really slower than Windows XP? It seems so. We did informal tests, booting both Vista and XP on the same hardware, and Vista was between 15% and 25% slower than XP in benchmarks. Then again, users moving to Vista on a new PC should in theory find that fast new hardware more than compensates. In practice, that is not always the case.

Digging deeper into the results is revealing. First, Vista is simply bigger than Windows XP, and runs background services which index your documents, maintain the hard drive, look for malware, perform backups and the like. Vista grabbed more than three times as much memory as XP, even before running any applications. When memory runs low, Windows uses the hard drive more intensively, resulting in dramatically worse performance.

Microsoft specifies 1GB RAM for most versions of Vista, but 2GB is the sweet spot.
Second, we noticed large variations in the performance results for different types of test. Pure number-crunching speed is similar on the two systems. Complex 3D graphics were close, and in some cases slightly better on Vista. However, basic operations like scrolling text in a window or drawing simple lines and shapes came out far worse. In some cases, XP was four times faster.

The reason is that Vista makes major changes to the way Windows draws on the screen. Vista handles graphics more in the manner of video games, using a software library called DirectX designed to exploit hardware-accelerated graphics.

DirectX is also used in Windows XP, but Vista uses it throughout, not just for games. Unfortunately there is a performance cost for traditional Windows applications like Microsoft Office. These generally use an older graphics library called GDI (Graphics Device Interface). In Windows XP this was hardware accelerated, but in Vista this is no longer true. Instead, they are mapped through DirectX. The new system also holds GDI windows in memory twice over, contributing to Vista's memory bloat.

Courtesy:thehindu.com
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