"No POST", "system won't boot", and "no video output" troubleshooting checklist

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Jun 26, 2009
Nice! This should help a lot of people with boot problems...
A thumbs up! :) :p
Kinda reminds me of the troubleshooting we were taught in a computer tech class I took...ah those good old times...


Apr 7, 2006
I think I have a new one...

Try waiting a few minutes between startups while bread boarding.

I had a HEC compucase with a nonstandard USB connector which when attached the obvious way would cause the computer not to boot. If it was removed, it would take a couple minutes until the system could fire up again, making tracking this down difficult. Turned out the color coding was not standard and they did not provide a manual. After I figured out the correct way to attach them, it was smooth sailing.
This post is a sticky and not your troubleshooting thread, Meef. Please copy that text to your own thread, then edit this post to delete the misplaced text.

If you would like someone specific to help on your post, send them a PM with the link.
I just sat down and really looked closely at this checklist for the first time in a while. It's really come a long ways and is an impressive tool now. I think it's better than I would have made it, and it really has proven invaluable for keeping our tempers under control. People are handled with patience because this checklist filters out the repetitive errors.

The TH forums are a happier place because of this checklist. Thanks again Shortstuff and everyone else.
Thanks Proximon! I don't deserve much of the credit for the checklist, but I have tried to update it occasionally with new troubleshooting ideas I see suggested in various threads. I recently updated #15 since I noticed a lot of people seemed to think plugging their normal computer speakers into the back of the motherboard would allow them to hear their system beeps.

Anyone who has troubleshooting ideas not included in the checklist can send me a PM. I'll check it out and add it to the checklist if it's worthy of it. :)


Oct 21, 2009
For #16, one additional thing to check carefully. It is simple and it would have saved me a lot of troubleshooting steps: For endless reboot--check to be sure that your reset button is not physically sticking. It happened to me on an Antec 900. It was actually one of the first thing I checked, but a couple of taps, apparently, wasn't enough. It wasn't until I bench tested my mother board that I realized that there was a problem with the button after all.


Oct 29, 2009
I have another addition to your checklist:

"Make sure that PCI-E cards and hard drives are powered adequately with the proper cables from the PSU".

I made the mistake of connecting too many devices from a single 12V rails cable because of which my PCI-E card did not receive sufficient power and the monitor went blank during startup. Strangely, there was no warning beep or post message on the screen to diagnose this problem - just a blank monitor! If your're stuck with a poor PSU with insufficient cables / splitters and plenty of hard / disc drives, this could easily affect you.


Dec 13, 2009
[quotemsg=10275416,27,43187]I would also like to add that a video card is not needed for a computer to boot. If there is a problem where the system wont even pass the BIOS screen and shuts down right after wards, remove the video card to see if it helps.

Tools for ANY one that builds their own computer.

http://www.alwayslowest.com/AL/index.cfm?fuseaction=shop.dspSpecs&part=2952576 - Power supply tester.

http://www.newegg.com/Product/Product.aspx?Item=N82E16819116039 - if you have an Intel 775 system

http://www.newegg.com/Product/Product.aspx?Item=N82E16819103195- if you have an AM2 system

http://www.newegg.com/Product/Product.aspx?Item=N82E16820134044 - Memory that will work in ANY DDR2 motherboard

http://www.newegg.com/Product/Product.aspx?Item=N82E16814161011 - PCI (not PCI express) video card. Newegg often has some great prices on open-box PCI video cards as well. Check your local ma-n-pa computer store, I'd be willing to bet that they have a working PCI video card somewhere in the back room for about $10.

Buying all of these components will let you diagnose almost any problem on TONS of different computer systems.[/quotemsg]

Can you please specify the exact item - since the links are currently dead for the AM2 system thingy.



Jan 31, 2010
DAMN. i wish i would have found this before i posted. I promise i looked far and wide for something like this before i did post. This didn't help me though..... sadface.
I made some changes to some of the steps. I specifically changed step #2 again to stress its importance. We're still getting people who claim to have been though the checklist that haven't performed the basics clearly listed in the checklist.

I don't know how to actually get people to perform all the steps instead of skimming through it not thinking it applies to them for some reason.
[quotemsg=10275541,153,113293]You can lead a horse to water ...[/quotemsg]

I know. That's very true. I was just wondering if it was something to do with the wording in the checklist or something. It seems pretty straightforward, but people still seem to have problems with it. Oh well, it is what it is...


Feb 17, 2010
Nice result of 1 year sharing thoughts and experiences :)

In another topic i read the "step 1 - measure voltages from your PSU" suggestions from Westom (see thread).

Wouldn't it be nice and useful to add a compact overview to this checklist of 'which wires should be within which voltage ranges', as indication/guide to know when your PSU is good to go, or good to go nowhere..?

I'll use your checklist tmrw to check my machine. Worked fine before we moved 2000km by car. The only things happening now are all fans and hdd spin up, but nothing more.. Guess it didn't like the ride in the trunk..

Great list, great initiative! :)



Didn't notice the title change until I read your post...

Just wish more people utilized this thread before posting about issues, so our first response isn't read this thread than get back to us. This is the best troubleshooting guide I've come across on any forum or website in dealing with boot/no video issues.

edit: grammer issues

Thanks tecmo34! It's a collective effort, but I've been spending the day doing some slight changes to the checklist. I hope the changes make it even better. But like you said, the problem is getting people to actually use the checklist before posting. :(


Feb 23, 2010
:bounce: I try to
No disrespect intended,,,please do not take my post wrong.

thanx again ! keep a finger on the escape.

[color=000cff]2.[/color][color=ff000c] Did you plug in the 4/8-pin CPU power connector located near the CPU socket?[/color] If the motherboard has 8 pins and your PSU only has 4 pins, you can use the 4-pin connector. The 4-pin connector USUALLY goes on the 4 pins located closest to the CPU. If the motherboard has an 8-pin connector with a cover over 4 pins, you can remove the cover and use an 8-pin plug if your power supply has one. [color=ff000c]This power connector provides power to the CPU. Your system has no chance of posting without this connector plugged in![/color] Check your motherboard owners manual for more information about the CPU power connector. [color=ff000c]This is easily the most common new-builder mistake.[/color]

Yep, I did that on my first build too. After 6 hours I finally noticed this little white square 4 pin connector hiding between a choke and the cpu cooler.


Apr 23, 2010
Excellent guide I have ever seen there is nothing more except if any of your device is not right which is rare. Mainly if ram is out of order so if nothing of the suggestion works check the ram by using it in another system or taking it to the service provider.
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