Viper Lair has posted an interview with Dan Snyder of Intel

If the application is not threaded, it will not see benefits from Dual Core. However, if the OS is threaded and it's running two non-threaded applications, we'll see some improvements as compared to a single core design. Say you have a virus scanner running and you open a 20MB PowerPoint presentation, a dual core CPU will do so much more efficiently.

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