Which is all well and good if your day job is with Geek Squad. However, if you're not a computer techie by training or inclination, it can be handy to have a small bag of tricks to work from. These all focus on the hardware side of things, more than the software side. Software deserves its own article. The flip side of hardware problems is that most of them are binary – you can either fix what's wrong with an obvious solution, or you can tell immediately that you can't fix it.

The first thing you should always ask, and this is gonna sound really basic, is "Is it plugged in?" Not just the power supply, but make sure that all the cables are seated properly on the back of the machine. Related to that, take a can of compressed air and blow the dust out of all the connectors and the interior of the computer. USB ports get flaky when there's dust on them.

After that, your next steps in diagnosing the problem are to ask questions: Does the computer show a POST message (a RAM check before it loads the operating system?) If the answer is "yes", then it's probably not a motherboard problem. If the answer is "no", then there's probably a loose connector on the motherboard.

While it's doing the POST check, you can hold down the ESC key and pull up a lot of diagnostics – make sure that it's seeing all the hardware on a hardware level before doing anything else. If it's not, it's time to unplug the machine, open up the case, and look for loose cables or cards or RAM. While you're at it, take that can of compressed air and blow dust out of everything, in particular the fan on the CPU and graphics cards. Make sure the heat sinks are clear of dust and obstructions, and blow the dust out of any fans in the case.

To see if a card (or RAM board) is loose, hold it lightly between your thumb and forefinger, and try wiggling it – if it gives at all, you'll want to pop it out (carefully!), blow dust out of the socket, and re-seat it.

A surprising number of Windows "blue screens of death" can be tracked down to poor heat circulation in a machine, and most of what's done here is meant to get you, by rote, fixing the obvious candidates for these sorts of problems.