On the other hand, if you have invested in a multicore system and are contemplating an upgrade, our multitasking test results are encouraging.
In this test we employ Windows Media Encoder to compress a video file in the background while we browse Web pages in Firefox in the foreground. On both dual-core systems, the test ran faster--29 percent and 31 percent faster on the Polywell and Micro Express systems, respectively--under Vista, indicating (as Microsoft has said) that the new operating system may be more efficient than Windows XP is at running multiple threads of code.
Frequently an OS upgrade comes with a hidden cost: To maintain an acceptable level of performance, you must upgrade your computer's memory. Microsoft calls for a minimum of 1GB of RAM on Vista Premium Ready PCs, and our tests indicate that that amount is a good starting point. The Aero interface can run on a PC with 512MB, but you have to switch it on; by default, if Vista finds less than 1GB, it installs with Aero switched off.
Just for kicks, we ran a few Vista-versus-XP comparison tests with 512MB of memory installed on our low-end test machines. Though the multitasking test didn't slow down much, the Photoshop times nearly doubled under Vista. The moral of the story: Don't run Vista with less than 1GB.
Moving up to 2GB produced significant gains only in our Photoshop test (see the "Vista RAM Boost" test report). On the low-end P4 system, the upgrade to 2GB garnered a 10 percent performance boost. The dual-core Polywell desktop showed a more modest gain of around 5 percent (PC World generally considers performance differences of less than 5 percent to be unnoticeable in general business applications); meanwhile, an HP laptop with a 2-GHz Core 2 Duo T7200 processor and GeForce Go 7600 graphics ran 21 percent faster with the additional RAM.
Our multitasking and Far Cry tests showed little to no benefit from the increased memory. However, we would still recommend upgrading to 2GB of RAM if your wallet can handle it, as the additional memory will give your system lots of room for future growth.