Some people will put power to a system several times during assembly and for experienced builders this may serve some purpose. For first timers though, it’s best to assemble a minimal complete system before powering up. Minimal because that way there are comparatively few potential sources of trouble, complete so that you can test everything at once and because the fewer times you have to put power to an open machine, the better..

If you’ve been working along with us you should now have such a minimal system put together. Briefly this includes a case with a motherboard in it, a processor (and its cooling unit) and some RAM plugged into the motherboard, hard and floppy drives installed, and some kind of video available. If your motherboard has built-in video, you might want to use that for this first try, even if you are going to install a video card later.

For this test, you’ll want to have the computer open, so that you can see all of the fans, and you’ll need to connect a monitor and a keyboard and a mouse (OK, you don’t really need the mouse . . .)

Monitors will either have a VGA, DVI, or a new HDMI plug (see picture, as they are a lot less apparent than PS/2 / USB by comparison). Most monitors use VGA connectors, and so most graphics cards have VGA output. If you have one type of plug and the graphics card has another, you can easily buy an adapter. Some cards even come with one.

There are two standard connectors for mice and keyboards; PS/2 connectors and the more modern USB connectors. Plug the mouse and keyboard in the appropriate slot.

Note: If you intend to install an operating system from a boot CD or floppy, or modify BIOS settings you will need to use either a PS/2 keyboard, a USB to PS/2 converter, or a motherboard that supports USB devices. Otherwise your keyboard will not work until the operating system has loaded USB drivers.

Once you have this all set up, it’s time to double check, then triple check that you have made all the necessary connections and that you haven’t left any foreign objects (where’s that screwdriver?) in the case.

POWER UP
Take a moment to check one more time that everything is as it should be. Make sure you’ve removed your wrist strap, turn on the monitor, then press the power button, and observe the inside of the open machine. (Do not touch any part of the inside of the machine while it is powered up – you will NOT die but your computer might.) The first thing to look for is that the CPU cooler fan spins up, if it does not, cut the power immediately. This fan should start up right away; something is wrong if it doesn’t and your CPU is in danger of overheating so stop now and troubleshoot.

NOTE: If you have a Gigabyte brand motherboard, the CPU fan may twitch and stop turning. Wait 10-15 seconds and it should start. If it does not, there is a problem and you should immediately cut power as stated above. Other fans such as case fans should turn on and spin.

If the CPU fan spins up, check that all the other fans that should be spinning – case fans and fans on the power supply and video card (if installed) are also spinning. Some of these fans may not spin up until a temperature threshold is passed, check your documentation if anything is not spinning.

If the fans spin, you can turn your attention to the monitor, what you are hoping to see is the motherboard’s splash-screen, usually featuring the manufacturer’s logo. If you see this, take a moment to bask in the glow, you’ve built a computer!

If this happy event does not occur, if smoke appears, or if the computer does not do anything, unplug the power cord immediately and check the steps above to make sure you have not missed anything. Give special attention to the cables and power connections. If the computer does appear to come on, but, you hear beeps, listen carefully to the beeps, turn the computer off, and refer to your motherboard’s manual for the meaning of the beeps. Some boards have an optional diagnostic device, usually a collection of LEDs, which when properly plugged in will inform you of the nature of the problem. Instructions for installing this as well as the meaning of its display should be in the manual for the motherboard. If the computer turns on but the only thing that comes on is your power supply, turn it off. This probably means something is shorted, and leaving it on could damage the parts.

If all is well it is time to turn the computer off, and close it up. Then you may want to turn it on again and set certain options in the Computer’s BIOS (usually by pressing ‘F1’ or ‘Del’ a few seconds after boot.) These options will be explained in the motherboard manual. In general, the default options are OK, but you may wish to set the computer’s hardware clock to the correct time and date. The BIOS is also where you determine the default boot order of the system, typically Floppy, then CD-ROM, then Hard Disc.

If you want a further quick test, before you install an operating system, you may find a bootable CD-ROM such as Knoppix extremely useful.

Earn a free Certificate of Completion for completing this course. Pass a 50-question test on this course with a score of 70 or higher and receive a certificate of completion. Visit our Computer Repair and Assembly Certificate of Completion page for more information.

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