First, it could be your video card. If you have a video card AND on-board graphics the try switching to your onboard graphics to see if your monitor will come on. The problem may be the video is NOT going through your card at all! Simply switch your video cable to the on-board socket (VGA or DVI). Another thing to try is to simply remove your video card and then boot up the computer. The on-board video should be the default video output when your third-party card is removed. If that solves the problem then you know something is most likely wrong with your video card.

(Note: Be sure to check your BIOS settings to make sure that the computer is trying to “see” the AGP, PCI or PCI-Express slot for video output and it’s NOT set to on-board video ONLY)

If you don’t have a video card, or you know that the video card is working properly then there are some more things you can try, like checking your hard drive. Yes, a bad hard drive can wreak havoc on a computer system, especially if it’s “shorting out”. The easiest way to check is to simply remove the hard drive and boot up the computer. The monitor should still come on to give your the “operating system not found” screen. Of course if you now see this screen then the monitor came on and there’s something wrong with your hard drive. I suggest getting a new one, IMMEDIATELY!

Now that you know that a bad hard drive can ruin a system, you should imply that other cards and adapters can as well. If you unplugged the hard drive and still have nothing, then you should begin to take out other non-essential items such as sound cards and USB cards and SATA cards, basically all PCI cards! You can even unplug your CD or DVD drives and floppy drives in order to strip it down the bare essentials; power supply, motherboard and video card. If you have your computer stripped down to those three things (or two, if your don’t have a video card) and the monitor still won’t come on then there’s only one thing left to try, a new power supply.

If you can get your hands on a friends power supply then you can check it yourself, otherwise you may need to bring it in to a computer repair shop and have it tested. Most shops have a small tool that they use to see if a PSU is good or not. If you find out that the power supply is, in fact, good then you know what the problem is, right? Yes, find yourself a new motherboard. If your computer is a few years old then this might be a good opportunity to upgrade with a new motherboard, processor and RAM, especially if you have a board with a socket that is no longer being made or hard to find.

1. Check to make sure the monitor is plugged in (electricity). There’s usually a light next to or around the power button that lets you know if it’s on or not. I swear to you I’ve had people who accidentally turned it off and didn’t know they had to turn it back on themselves

2. Is the computer on? The computer is usually in the form of a tower. If it’s on, then turn it off for 5 seconds and then start it up again. You can just push the power button or unplug it, whatever suits you best.

If the monitor does come back on then it could have been just a one-time glitch. If it keeps happening then I would suggest noting when it happens. There are two common problems associated with the monitor not responding; one is when it goes to “sleep” and the other is when the computer boots up.

If you are using the computer then leave for while and come back to the monitor not coming on, then you need to check your monitor power settings via the “power options” control panel. First see if hibernation is enabled, if it is then turn it off. Also, see if system standby is enabled; if it is, then set it to “never”.  Make sure to click “OK” then restart your computer. If the monitor problem goes away then problem solved! You may try setting system standby again, but try to leave hibernation truned off. I have never liked hibernation in a desktop computer because it almost always causes problems.

If the monitor sometimes doesn’t come on when you you boot up your computer then I might suggest trying different RAM, if you have any. More often than not bad RAM is responsible for a monitor not turning on during a bootup. If you are not familiar with how to change RAM or just simply scared to do so then by all means take to a local computer repair person and have them check it out for you. There may be other things that cause the monitor to not come on but 95% of the time it’s due to faulty, or bad RAM.

Just a note: RAM is a heck of a lot cheaper than a monitor. So, before you shell out big money on a monitor (if you think it’s dead) ask a friend or family member to borrow their monitor just for testing purposes. If the borrowed monitor works on your computer then the odds are your monitor is dead. On the other hand if it doesn’t work then you just saved yourself some money because the monitor was not the problem. (Of course, you’ll now have to spend that money on finding out exactly what IS wrong!)