Want to learn how a PC works? Build one yourself. It's not only educational, but it's also a great way to save money on a new system.
For example, Circuit City has a Biostar N68S+ quad-core bare-bones PC kit for $199.99, plus around $12 for shipping. You get (nearly) everything you need to assemble a complete desktop for considerably less than if you bought a prebuilt system off the shelf.
Let's start with what you get, then talk about what you don't. The kit comes with a 400-watt tower case, a Biostar N68S+ motherboard, an AMD Phenom X4 9100e processor (with cooling fan), 2GB of PC6400 RAM, a 500GB hard drive, and a DVD burner.
My only real complaint with that load out is the RAM, but you can easily (and inexpensively) drop in a second 2GB module if you feel the need.
The kit doesn't come with a keyboard or mouse, a monitor, or speakers. The idea here is that you probably already own that stuff, and like the stuff you own, so you'll use your existing gear.
Also not included: an operating system. If you want to keep things on the cheap, you could install any number of free Linux distributions (like, say,). Or, if you already own a full version of Windows, you can install that.
For many users, the big downside to a DIY system is the lack of tech support. Each component in the kit carries its own warranty, but if you have a problem getting everything to work, well, you're sorta outta luck. But this kit has an average rating of 4.1 stars from a whopping 900-plus users, so I reckon everything goes together pretty well.
What are your thoughts on DIY PCs versus the off-the-shelf variety? I'll admit I usually take the latter route, if only for the sake of convenience, but I've built plenty of systems in my day. It's fun!
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