Did I mention that this is going to be an all-encompassing guide on RAM? No? Well it is, so those of you who already know what RAM is for and how it works can skip ahead.

IBM's latest supercomputer Watson has 16TB of RAM. Overkill?

You may have noticed the absence of any recommendations relating to 3, 6, and 12GB solutions. That's because achieving 6GB of RAM, for example, requires an odd combination of DIMMs (memory sticks). In this example, you would need three 2GB DIMMs, meaning you would not be able to run them in a Dual Channel Configuration.

So you've figured out how much RAM you need, but how fast should it be? Well, for the best results, it should be as fast as your motherboard allows. This would be for anyone who wants to be on the bleeding edge of performance, like a hardcore gamer. The average consumer won't have much need for the fastest RAM in the world, and that stuff can get pretty expensive. Instead, DDR3-1600 is a nice middle ground. It's still fast, but not so fast that it costs a hefty premium.

But wait! Before you run down to the store and fork over all of your hard earned money for fastest rated RAM you can find, there's one more thing to consider: Latency. Memory modules are also rated in "Timings," generally a sequence of numbers, such as 9-9-9-24. The most useful of these is the first number known as the CAS Latency. This is the number of clock cycles it takes the RAM to access a column of data (the smaller the better), and in conjunction with the speed of the RAM, can be used to calculate its response time. The formula is

A SO-DIMM is a miniaturized version of a regular DIMM, generally used in laptops and other low profile systems. Just like a full sized DIMM, it's important not to mix up DDR, DDR2, and DDR3 modules.

WILL A DDR3-2000 DIMM WORK WITH A DDR3-1600 MOTHERBOARD?