New mobo: No post/boot/monitor signal

dreid168269

Prominent
Sep 3, 2017
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Good morning,

I have a pc that suddenly stopped working a few weeks ago. It was being used to watch some Youtube videos and then it shutoff completely. After that it began to reboot, but only made it a few seconds showing the board manufacturer before shutting off again. It would continue this cycle indefinitely without intervention.

I began troubleshooting by removing parts from the board and originally had thought it was the GPU. However, I have a similar GPU in my pc and after swapping them, the same problem occurred. And the other GPU works just fine in my pc. I did notice that after removing the GPU, the system stopped the unending reboot cycle. Also, when I installed my GPU into the trouble pc, it was able to make it into BIOS, but upon restarting from there, the problem continued.

I tried removing memory modules as well, but the GPU seemed the best indicator of where the problem lies.

I have since purchased a new mobo and now I have my current issue where the system will not boot/post or send a signal to the monitor.

I will note that I have gone through all the steps here: http://www.tomshardware.com/forum/261145-31-perform-steps-posting-post-boot-video-problems at least once. Some a few times just to double check.

System specs as follows:

8G DDR3-1600
NVidia GeForce GTX 650 / 650 Ti
480W 100-240V/50-60Hz

Old Mobo:
Asus P8Z68-V LX
LGA 1155/H2 socket

New Mobo:
Intel DZ68DB
LGA 1155/H2 socket

Not sure about the cpu at the moment.

Also, through all the testing, the new Mobo has an onboard buzzer, and not once did I ever hear it beep. Even with all the memory sticks removed.

Any help is much appreciated.

Thank you.
 


Sorry to hear you're having problems, Sounds like you've been working on this a while.
As a tech, this is what I would do:
Unplug / disconnect EVERYTHING from the MB except for the CPU, CPU cooler and case wires. Then, if you don't already have one, get or borrow a internal PC speaker and connect that to the SPK connections on the mainboard.
Then, press the MemOK! switch (next to the power connector on the mainboard) to reset the BIOS to default settings, the power it on. What SHOULD happen is you get a single, long repeating beep which is the computer telling you there's no RAM in the system.
As long as that works, power off and insert the minimum number of memory pieces needed to boot, plug the monitor cable into the on-board video (VGA, HDMI or DVI should work) and power on again. What should happen is you get one short beep and a display on the screen showing the BIOS.
Then, rebuild the system one piece at a time until it fails. Once it fails, if yo go back one step and it works, the last thing changed is likely your culprit.
If NONE of this works and you still get nothing, the most likely culprit is the power supply. Yes, they do go bad.

Good luck!
 


Thank you, I will give this a try. The curious thing is the new board already has a speaker/buzzer on it that looks just like the standalone speakers and there is not a MemOK button that I can locate. The old board has one, but no speaker.

Either way, I'll try what I Can.
 


If you are referring to clearing CMOS (as that's all I found when searching how to reset the BIOS without a monitor), then I have already done that a couple times as well.
 


With nothing on the board save the fans and the cpu, nothing happens. No beeps, nothing. The only indications that anything is on are the fans and the standby led on the mobo. I am about to send the board back for the warranty. I can't think of anything else that might be wrong other than the cpu. That will be the next step.
 


Yes, there is a green standby led on the board that is lit and all the fans turn on when I turn on the power.

Update: What I should have done on day one is check the power supply. I was being willfully naive about it being the problem. I swapped them between pcs, and the problem began immediately on my working pc as soon as I turned it on, and the other pc started beeping like it should.

With that said, the beep pattern was like this:

2 consecutive beeps, approx 1 sec long each. Repeated once.

The only things installed on the board being power, fans, and memory.
 


Curious that it is registering as a video error. I even tried to plug the monitor in to onboard video. In the mean time, I am going to wait until I get the new psu, because I really don't fancy swapping the working one between pc's anytime a new issue comes up that I need to search to diagnose. I'll report back when I have it.
 
Ok, the new PSU is installed and working. Now, the issue is a BSOD shortly after the computer boots. It makes it to the beginning of the windows logo (Win 7) where the dots start to swirl into view, then it freezes, crashes and reboots to offer Repair mode (which did not succeed). The BSOD message says to uninstall any new hardware (well, it's the whole dang mobo and psu that's new). Leaning toward reinstalling the OS.
 
at this point, you may have to. before that, though, see if you can boot into safe mode. If you can, try removing all the devices from device manager and rebooting.
 
I was unable to boot into Safemode. I tried using the command prompt through the Startup repair, but the same BSOD issue occurred. I was thinking of hooking up the hdd to my working pc to try and retrieve any files before reinstalling.

Update: I have now run into another problem. I went ahead with the reinstall, and as far as I can tell, it was successful. However, now the pc won't turn on. There is no response at all when I press the power button. No lights, no fans, no sounds, nothing. I'm about at a loss at this point.
 
okay, on my pc this can happen if windows is powered off without shutting down properly and, when it happens, the only way I get back to normal boot is by removing the RAM, power cycling, then putting the RAM back in. It's annoying as heck but it works. Give that a try.
 


Unfortunately, this did not help. I unplugged the power button from the board and plugged it back in as well. I am about to give up.