Strangestranger has it right. If there was such a thing as a 10Ghz Octo-core chip, it probably wouldn't zip everything at super fast speeds. Your limited to whichever components are being used. For installations and zipping your HD is used and is certainly the slowest component. It doesn't mean you should run out and buy the fastest hard drive you can, because you might only squeeze 2% more CPU out of it. 25-35 is just fine for zipping and such.