Gizmodo compared the performance of Windows Vista, Windows Vista with SP1 RC1 and compared it against Windows XP SP2. All benchmarks were done on a dual quad-core 3.16GHz Penryn HP xw8600 PC with NVIDIA Quadro FX 4600 workstation graphics, 4GB RAM memory and 15k RPM SAS hard drives.
In some benchmarks Windows Vista is slightly faster than Windows XP but in tasks like transferring files over a network and HDD speeds the new operating system is significantly slower. In Windows XP it only takes 3 minutes 37 seconds to transfer 1.37GB while in Vista this takes 12:58min and with the new service pack even 15:41min! The HDD transfer speeds in Vista are also pretty bad:
Did Vista have speed trouble? Well, yes and no. When we ran the industry-standard PCMark05 benchmark on both Windows XP (SP2, we hear SP3 will be faster) and Vista, Vista came out ahead by a sizable margin on exactly the same machine, scoring a 10,403, compared to XP's score of 9024, a 15.28% speed increase for Windows Vista. That's a noticeable difference. How did Vista feel, speed-wise? We immediately realized we were dealing with increased speed over XP, over a long weekend of mousing around the PC, running Photoshop and Adobe Premiere, running benchmarks and browsing websites.
The only downside we noticed with Windows Vista was when we tried to transfer a large folder full of files over our 100Base-T network. While XP was able to transfer the 1.37GB folder containing 2606 items in a quick 3:37 (minutes/seconds), the Vista transfer seemed to hesitate at the end, taking a leisurely 12:58 to perform exactly the same copy from one PC to another over our network.