That sounds like an outdated software requirement. With the changes in CPUs that do more with each clock and more than one core, such are often outdated requirements. Tell more.
I don't see a complete NEW PC for that price. You may have to look at used but let's clear up where that 3.0 came from.
Example. http://computers.woot.com/plus/envious-hp-envy-desktops-all-in-ones?ref=cnt_wp_3 and it's CHEAPEST refurb is over your budget.
Bob
I am looking for a computer that has Intel and has 6-8gb of ram and around 3ghz of processing and I have found a few but I have seen the Intel turbo boost and it says it can go up to 2.7 on some, does anyone know any that go to 3.0 or more that are within the 3-400 dollar range?

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