Easy enough, right? Unfortunately, you'll need to have a second computer on hand to do a bit of online research: Not all motherboards use the same beep codes, and the manual that came with your part or system may not list the codes that it uses.
Worse, some motherboards lack beepers or speakers altogether, though they usually do have internal connectors for speakers. Such motherboards usually have diagnostic LEDs on the motherboard that provide the same information, but you'll have to open the case to see them.
My System Won't Start at All, and Pressing the Power Button Has No Effect
Hello, hardware issue. Did you just finish working on the inside of your system? Did you remember to flick the switch (if it exists) on the back of your power supply to turn the juice for your rig back on? Did you turn on the surge protector or power strip that your system may be plugged in to?
If those items check out, try reseating your cables in case something internal got bumped out of place or left not-all-the-way connected. If your system is still unresponsive, try removing and reconnecting your video card, your RAM, or even your CPU and cooler.
Your power supply is another possible culprit. Use an inexpensive power supply tester (these run $10 to $20) to verify that your power supply is working. And remember to check the switch itself to see whether it is properly connected to the motherboard's front-panel headers. I've seen the tiny connector that attaches the power button to the motherboard work its way loose, for example. If your motherboard has a power button on it, press that button to see whether it can start your system.
My Monitor Has Color Issues or Suddenly Goes Blank (No Display)
You might have connected your monitor to your desktop without using the screws on your DVI or VGA cable to lock the connector into place. Your first troubleshooting step should be to disconnect and reconnect your cabling; after that, try using a different cable (or borrow one from a friend) to see whether you can resolve the issue easily and inexpensively.
If you've ruled out the cable as the source of the problem, turn your attention to the connector. Assuming that your graphics board or motherboard supports a different connection type, try switching to one of the other connectors: DVI, HDMI, DisplayPort, to see if that fixes the problem.
Turn off your PC's power, and unseat and then reseat your graphics board (if applicable) to see whether a loose PCI connection is causing your display woes. Funky colors on your monitor could be an early sign that your video card is overheating (or going bad). Check your card's fan (if applicable) to confirm that it is spinning freely; if it's caked with dust, turn of your computer, touch the fan with your finger to prevent it from spinning, and blast it with some compressed air.