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

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Very useful! Big thanks to shortstuff for the link. Does anyone have a gigabyte board? I have the ga p55 usb3 one and everytime i turn on the computer the phase leds go on and the colors are yellow red and green. What do these mean?
 

;p

YES! Definately DO have an answer, for ya ...

... You look up your board, at newegg, and follow the manufacturer's info tab >> product link to the Gigabyte product page ... You then go to support and download the pdf manual and you will find that all those color codes are listed ... right there in the mobo manual !!!

I wish you had started a new thread, so you could award me the "Best Answer" Points ... Oh, well, ... a "life of service" ...

= You are MOST welcome ! =
 
Great info! It didn't directly address my problem, but it did get me looking in the right direction.

For item #2 - My PSU (Dioblotek DA500) came with an 6/8 pin connector, MB (Gigabyte MA785GT-UD3H) had a 8 pin CPU 12 V connector, seemed simple, but no boot. :fou:

Disconnected everything, checked PSU, even pulled out CPU, bent pins in the process. :cry: (Still worried if I should take it apart to put in new thermal grease). Put it all back together and went to bed.

Next day after work, looked around on the net, and found this thread, looked at the MB manual for the 10th time, then the PSU manual, looked at some yellow and black wires really closely and had the a-hah moment and plugged in the 4-pin connector to the 8 pin plug. Hit the power button and all works fine. :wahoo:

Don't know if this is that common, but it might help someone.
 

If you look carefully and compare the 4/8 pin CPU power plug with the 6+2 PCI power plug, you will notice that they are wired differently. Plugging either into the wrong plug (and you shouldn't be able to do that) will short the 12 volt PSU output to ground. If the PSU works properly, there's no problem. The PSU should detect the overcurrent condition and electronically shut itself down before it fries itself or the motherboard.

shortstuff, great job with the pictures. :bounce:
 
Great work thanks to those who initiated and contibuted.

My suggestion: Item #15 should be a warning at the beginning of the article without an item number. This warning may also include:" A human body may generate 300 volts of electricity but many components can be damaged with much less voltage. " In fact, the second part of the sentence is already there in item #15.

Regards
 
thank you thank you thank you thank you a million times. I just finished building my first computer and couldn't figure out y it wouldn't post. I read this :

"2. Did you plug in the 4/8-pin CPU power connector located near the CPU socket? 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. This power connector provides power to the CPU. Your system has no chance of posting without this connector plugged in! Check your motherboard owners manual for more information about the CPU power connector. The CPU power connector is usually referred to as the "12v ATX" connector in the owners manual. This is easily the most common new-builder mistake."

I figured out it wasn't plugged in and now it posted. thank you so much. I was just about to redo my whole computer. (lol)
 
I just troubleshot (troubleshooted?) my new build and figured out it was the PSU using just this thread and a few others scattered around THforums. Thanks for saving me/you the trouble of me making a thread and doing what I eventually did on my own 😀

You guys rock.
 
The CPU power connector is usually referred to as the "12v ATX" connector in the owners manual. This is easily the most common new-builder mistake.
Click to expand...

I've been building my own computers since I soldered my first XT together in the 80s. What's worse is that this is the 4th of this almost exact machine I've built in the past year or so.

And still, I skipped reading the manuals and I missed this. -slaps head-

So, you guys don't let this sort of thing get ya down. It happens to the best of us.

(THANKS for the awesome post. It was the first google hit and it fixed me!)

Raymond.
 
 



I just had this same thing happen to me with an ASUS P6X58D-E MB. It had a black cap over 4 of the 8 pins (which should have clued me in). There was *NO* mention of a 4 pin cable working on this MB in the manual and it *specifically* said it would not boot without an 8 pin cable.
 
Just reread this thread, and realized it is nearly my one year anniversery since my first build. I was hooked from the start and have built by myself or assisted in a building about a machine per month since then.

It was fun to reminisce about all the "problems" I have had in these dozen builds. More specifically, I have "failed" at steps 7, 8, 12 and 15. I put "problems " and "failed" in quotes because I memorized this checklist almost from the start and have never have spent more than 10 minutes troubleshooting what I forgot to do (OK, so it is going to take longer someday when I get a DOA power supply).

The point I want to make is that this thread (and select others at Tom's) take all the trepidation, fear and worry out of the process, making building computers a wonderful hobby for me, and a great year.

Thank you shortstuff_mt. Thank you Proximon.
 
I have a newly built tower that is having alot of the issues ive read on here and i have tried almost all of the solutions to no fix. I have a gigabyte s-series g41m-es2l motherboard. A gtx 460 video card. Corsair 650 watt power supply. 2 2gig sticks of ddr2 ram. Intel core2 e8400 cpu. The tower powers on for around 10-15 seconds but never puts a picture on the monitor. after the 10-15 seconds the tower will power off for a few seconds and power back on. It does this repeatidly. I Have replaced the motherboard twice, video card and power supply. I took both sticks of ram and rotated them around also took them out and put them in another tower and worked fine. The tower worked fine for around a week or so and this started happening. Been doin this for over 2 months now and i cant seem to fid the answer.

Also just before this started i blue screened a few times and in the event log i was getting event id 41. But now i cant even get anything to turn on or even get into bios due to the screen not booting up or anything and the tower constantly rebooting.

As far as the things ive tried besides rotating the ram and replacing the various parts. ive went through ur checklist and made sure all the parts were hooked correctly and pressed all the way in. unhooked and rehooked almost everything. took the pwer supply video card and ram and put them in another tower to check them and they worked fine. At the moment with the original purchase and all the replacement parts im up to around 1500$ spent. Any suggestions would be much appreciated.
 
Hey guys,


Just wanted to say a big thanks to shortstuff for compiling all the info and giving me something to go on after my beloved comp died.Nothings more infuriating when trying to ts an issue by collecting similar experiences on the net than threads that have no conclusion ie they fixed their issue without telling people how they done it!

My specs, so yas get an idea what i was dealing with:

Asrock X58 Supercomputer mobo
i7 930 quad 2.8ghz
Radeon 5870 1gb toxic vapor chill oc version
8 gigs of corsair xms3 ddr3 2000mhz ram
160 gig seagate raid 1 array with windows 7 64bit installed
1tb wd black edition sata hdd
Corsair Wtx850 PSU

So my story goes like this,i'm a fairly experienced PC user for some years but only last year did I have cash to build the pc I've always wanted(Had a few shitty dell pc's before this)Im a fair beleiver in not giving up when a computer breaks like reinstalling windows for me, means ive failed lol.Any way since ive built my own ive been bit by the overclocking bug and i'll admit that even now ive still not been able to get the perfect oc for my specs(anybody willing to give me recommended bios settings so i can clock my ram at stable 2000mhz would be appreciated!)

Soo I had been a bit overzealous with my OC processor was up to 4gighz ram about 1800mhz and i think i had blindly changed some settings think was qpi to too high.

Then I had the brightidea to torture test my rig using Prime 95,rig died instantly!No error messages no bsod power just left
the machine!So I tried to restart and nothing, led's and fans powered for split second and that was it,could not even reach bios.
So in cases like this you would naturally clear the cmos via the jumpers and that didnt resolve it,so i decide to remove the cmos battery left it over night and still the same issue(at this stage i got really worried)So I started checking forums for possible solutions thats when I found this thread!

Soo I breadboarded the system and found when I shorted the power switch all the fans would come on so I started adding components one by one at this point I was getting no bios beeps by the way,and only when I plugged in the 12v atx did she decide not to power up,same issue as b4 fans would spin for split second then nothing.So i removed all components except one stick of ram and decided to see if clear cmos jumpers would have an effect,computer would behave the same fans for a second again,and that was when I realised that if I kept hitting the clear cmos jumpers in quick succession the fans would
speed up slightly,so i hit it about 15 times and lo and behold she jump started all the lights came on fans were spinning correctly and the bios speaker started beeping like crazy!Rebuilt comp entered bios loaded previous stable settings and it booted up without any issues!

So my question is this How or why did it boot using this method? because I have seen no solution like this on the web.


I hope this helps anybody in a similar situation to mine.

Thanks guys
 
These are great suggestions! Thanks for the photo of the case speaker -- I had gotten one with my case, but no instructions what to do with it. Going back into the box to install that, I reset the CMOS jumper ONE MORE TIME, as suggested. And disconnected the reset button connection, as you also suggested (who needs it?). Now it has POSTed, got its widdle BIOS set up, & works like a peach!
I've installed the latest Ubuntu OS, & I have to say, it's easy, fast & pleasant!
Thanks for your help!
BlueAZ
 
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