Question PC is making beeping sound and not powering ON

[Proximus77]

I have a custom made PC (not assembled by me) with the motherboard Intel DH87MC, 4 GB RAM Windows 7. It was restarting again and again randomly firstly it was during normal running of windows then this became shorter and shorter and then it started shutting down and rebooting after 9-10 seconds. Here are the steps I tried:

1. Changed RAM and its sockets
2. Checked PSU
3. Checked if processor is maybe overheating, pasted fresh layer of thermal grease
4. detached all auxiliaries e.g. keyboard, mouse, HDD, DVD-R/W
5. removed CMOS battery for 10 or more seconds
6. changing position of BIOS jumper and pressing power button for 30 seconds

nothing worked and the new development is that it now starts for only 2 seconds and give a single loud beep. I have checked all beeping codes information available on internet but nothing relates to it.
As a reference, here is attached a 8 second video of the error, please take some time to watch it, any help or suggestion is really appreciated.

 

[Barty1884]

1 beep should be a successful boot.
https://www.intel.com/content/www/us/en/support/articles/000005473/boards-and-kits.html

However, I can see from the video you do not have the 4pin EPS connector connected - it's handing from the PSU below the rear fan.

 

[jamesanyoung]

try it again with your CPU power connected, otherwise it sounds like a dead motherboard.

Do you get any info when you connect it to a display?

 

[Proximus77]

1 beep should be a successful boot.
https://www.intel.com/content/www/us/en/support/articles/000005473/boards-and-kits.html

However, I can see from the video you do not have the 4pin EPS connector connected - it's handing from the PSU below the rear fan.

First of all Thank you for your quick reply and keen observation, I actually received it in such condition from my friend (helping him ) this EBS connector interfaces to PSU?
Let me try this and get back here to post result.

 

[Proximus77]

try it again with your CPU power connected, otherwise it sounds like a dead motherboard.

Do you get any info when you connect it to a display?

At first, it used to go upto Intel logo and before it restarts again but after I unplugged all connections of PSU to just make sure to be inserted properly and firmly and after all the steps I mentioned in my original thread, It now does not remain power on for ore than 2 seconds as shown in video, So to sum up no info is displayed

 

[Barty1884]

First of all Thank you for your quick reply and keen observation, I actually received it in such condition from my friend (helping him ) this EBS connector interfaces to PSU?
Let me try this and get back here to post result.

Yes, the connector is hanging where the red arrow points, and needs to go where the yellow circle is.

 

[jamesanyoung]

Hard to diagnose without being hands on. I am going to blame the motherboard for this one. The Mobo has to send a signal to the PSU to tell it to power everything, and its sounds like this signal is not being sent or received correctly, and the system shuts down.

If you have already confirmed the PSU and RAM is fine, then the Mobo is probably to blame.

 

[Proximus77]

Hard to diagnose without being hands on. I am going to blame the motherboard for this one. The Mobo has to send a signal to the PSU to tell it to power everything, and its sounds like this signal is not being sent or received correctly, and the system shuts down.

If you have already confirmed the PSU and RAM is fine, then the Mobo is probably to blame.

OK, Thank you. one last thing to do as mentioned by Barty1884, I will check it first thing and if it still has some error then maybe its to time to say goodbye to mobo. While we are on the subject can anyone please suggest alternative mobo for the one I have (DH87MC intel) as it is old & discontinued and very difficult to find in market.