This is a very old thread, but I'll offer some advice on the Intel i-Series.

The LGA 1150 is a great socket. I build a basic web surfing machine with it last month. The cheap i7s on eBay are LGA1366. You can literally buy an i7 CPU for $25, but good luck finding a motherboard. They'll cost well over $100. For that cost of the board, you can easily build an AMD FX-6300 based machine or an entry-level i3 machine that will have a better upgrade path.

The LGA1366 is a very old socket, and there are no new boards for it.

The market on Core 2 Duos is setting. They're abundant and cheap, but for the price, I think you can do better.