Question Broken Motherboard ? Flashes LED's for a split second then nothing until i unplug the PSU.

[ScarLeRenard]

Hello,

I'm having issues with a X299 motherboard i have, to a point i created an account here just for that.

The thing is, the motherboard, once plugged to a live PSU, flashes it's stand-by LEDs ( That line most motherboards have down at the bottom left + Also a green light just under the I/O ) for a split second then shut itselfs down.

No POST, no boot, no fans spinning, no nothing, not even a single light on the case, it's like the *** is bricked. [Moderator edit to remove profanity. Remember Tom's is a family friendly Forum.]

... Aside from the GPU, which has it's red warning LEDs still on when you unplug the PCI-E cables ( Picture taken from Google but you get the point, same LEDs, but solid red ).

Aside from that, nothing gets current, i would've said at least the 5V seems to work but no, since it should also work for the motherboard stand-by lights.

Unplugging the PSU for a bit, then replugging it and turning it on will make the same effect again.

Problem is, i tried everything, changing PSUs, running the motherboard with or without CPU, same with the GPU, RAM and even battery.

And the result is always the same.

I'm starting to lose hope, really.

If anyone has any kind of advice, I'd love to read it, anything can help at this point ...

 

[Ralston18]

Update your post to include full system hardware specs and OS information.

PSU(s): make, model, wattage,age, condition (original to build, new, refurbished, used)?

If modular PSUs - did you use any cables from PSUs other than the PSU that was installed?

Disk drive(s): make, model, capacity, how full?

When you stated "The thing is, the motherboard, once plugged to a live PSU, flashes it's stand-by LEDs" do/did you mean that the PSU was already powered on when you connected the motherboard?

Versus having all power off, making the cable connections within the build, and then turning on the computer.

For the most part, the problem could be a thermal shutdown.

What thermal paste was used and how was the paste applied?

 

[ScarLeRenard]

Update your post to include full system hardware specs and OS information.

PSU(s): make, model, wattage,age, condition (original to build, new, refurbished, used)?

If modular PSUs - did you use any cables from PSUs other than the PSU that was installed?

Disk drive(s): make, model, capacity, how full?

When you stated "The thing is, the motherboard, once plugged to a live PSU, flashes it's stand-by LEDs" do/did you mean that the PSU was already powered on when you connected the motherboard?

Versus having all power off, making the cable connections within the build, and then turning on the computer.

For the most part, the problem could be a thermal shutdown.

What thermal paste was used and how was the paste applied?

I don't think OS matters as it can't even POST ( But in any case, 3 Seagate HDD's and 2 Samsung SSD's with both Windows 8.1 and 10 on them ).

Thermal shutdown usually happens seconds after the shutdown, no ?

The thermal paste was applied generously, it's some Arctic MX-4, and i tried it without cooling solution too, same results as well.

The PSU i used is a BeQuiet Straight Power 11 Platinum 1200w, it is known working as i've used it for gaming less than 48h ago ( On a different MB & CPU, obviously ).

And obviously, used it with the same cables as before, the ones provided with the PSU.

The PSU is less than 2 years old.

Other than that, the rest of the parts are :

MB - Gigabyte X299 UD4
CPU - Intel Core i9 9820x
GPU - Asus TUF RTX 3080 Ti
RAM - Corsair Vengeance LP - 32 Gb ( 2x16 )
Watercooling - Corsair H100i RGB Platinum

All parts are second-hand, only the motherboard and CPU are new to the build.

For the explanation : Nothing happens when you plug the PSU to the wall, but, when you put the PSU switch to the " On " position, only then there's something happening.

The thing being the green light + amber lights ( Probably stand-by lights ) flashing for a split second.

After that, nothing happens.

In any case, if the GPU is plugged to the PCI-E lane, but without proper PCI-E cables, the little red light i mentionned still turns on whenever the PSU is live ( Meaning that there's still some sort of 5V going through the motherboard up to the GPU via the PCI-E lane ).

And yeah, i plugged the motherboard and all of it's cables and connections when the power was off, as always.

 

[Ralston18]

Reference:

"if the GPU is plugged to the PCI-E lane, but without proper PCI-E cables" - what do you mean by "without proper PCI-E cables".

= = = =
There is still quite a bit that you can do with respect to troubleshooting and, hopefully, finding a fix.

This motherboard?

https://download.gigabyte.com/FileList/Manual/mb_manual_x299-ud4-pro_1001_e.pdf

(Confirm that I found the applicble User Manual.)

Read through the entire manual and keep in mind what you have noted thus far along with the various things you have tried in order to fix the problem(s). Pay close attention to all fine print, note, caveats, and warnings.

That the PSU works well on another system is good. However, systems are different - It does not take much to have a PSU begin to falter and fail. Some threshold condition. The PSU remains, in my mind, a potential culprit. Amoung others....

First, take a careful look at the LED's and their respective meanings when lit. (Referencel physically numbered Page 13 in the manual). It is very important to know what each LED is "monitoring" and what is being indicated by each individual LED and also collectively by all LEDs.

Second, double check that all cables, cards, RAM, jumpers, and case connectors are indeed correctly installed and firmly in place. Pay close attention to the Front Panel case connections. Page 19. I also noted that the preceeding paragraph references the D-LED jumper configuration for 5 or 12 volts. Check the jumper.

Third, noted that you changed the CMOS battery. Did you clear CMOS per the procedure provided on Page22?

And "The thermal paste was applied generously,". More does not mean better so that is a potential issue. I am unable to say if the paste itself could be the problem. However, that cannot be excluded and needs to be considered.

FYI:

https://www.tomshardware.com/best-picks/best-thermal-paste

Others may post comments regarding the paste itselft and the application process.

Simplify the build as much as you can - just the basics and start over.

And remember that PSU's can be tested to some extent if you have a multimeter (or know someone who does). Not a full test as the PSU is not under load but any voltage out of tolerance makes the PSU suspect.

https://www.lifewire.com/how-to-manually-test-a-power-supply-with-a-multimeter-2626158

Lots of work and effort but that is often what is necessary.

 

[ScarLeRenard]

I tried simplifying it down to PSU + Motherboard only, same results.

As for the motherboard manual, it's just not the pro model, it's discontinued while the pro model is the updated version.

But they're basically the same.

All cables and connections are always firmly inserted, i double check for that every time.

Cleared CMOS multiple times and changed the battery too, as mentioned, i even booted without it, doesn't change the outcome.

Thermal paste really shouldn't be the culprit as i have put enough of it in my opinion, but none of it went outside the IHS of the CPU.

In any case, booted without thermal paste, and even without CPU as mentioned, same results.

As for the LED jumper, it's for external LED strips i believe, the ones i was talking about were the integrated ones on the motherboard.

In the manual, these ones are not referenced, though.