If you are looking to upgrade to a dual core rig, but want to do it cheaply, then Intels 8** series may be for you. We are taking a look at the 820 D, a 2.8GHz chip with 1*2MB cache. What makes it a great value is the fact that it overclocks to almost 4GHz on air. But compared to other similar chips on the market, is this one worth your cash?