What is the difference between these two? AMD K6 and AMD K6-2 Are they the same socket? To upgrade my computer, where is the best place to get compatability info?

There is no difference between the two. All you will be able to buy on the market is AMD K6-2. A very good chip. If you have the book on your motherboard, the the supported processors will be listed. To get an updated list, you need to visit the web site of whoever made the motherboard. You should be able to get y0our jumper settings here as will. Good Luck

The K6 was one of the original CPUs offered by AMD, and had a higher core voltage and different cache structure than the subsequent K62, and only ran @ 66mHz. They were replaced shortly thereafter by the K62 line. You won't find the original K6 CPUs available anymore, but there are still plenty of K62 products available. And no, the motherboards for the 2 versions were different. As far as compatability goes, you should know that AMD has said that they'll be discontinuing the K62 line (though not stated exactly when) now that their Duron, Athlon and Thunderbird processors are widely available (with more to follow). My advice is this with regards to upgrading: Think AHEAD. While you can still purchase/build a K62 system, you'll be limited to 550mHz with no possibility to upgrade from that in the future without replacing both the motherboard and CPU. OR....you can be smart and spend a little more on a system with an AMD Duron processor and Socket A motherboard now, with the option to upgrade to an Athlon [also Socket A] processor later without changing your motherboard. The choice is yours, and without knowing how or what you use your computer for, that's the best I can offer ya.