Asus P9X79 Pro: Powers on, then off, then on, then off...

[Mike486DX]

Hi,

Tried building a new rig today and failed.

Asus P9X79 Pro
Core i7-3930k
8gb DDR3
GTX 750Ti
Seasonic Platinum 1050w PSU

So as per the thread title, when I power up, the fans spin for about half a second, then the board powers off completely. No VGA, no POST, no warning beeps, just on, fan spins, then off.

Then about 3 seconds later it comes back on again, same thing, turns back off again.

This loop is endless.

Here's what I've tried
- Reseated CPU
- Reseated all power cables including CPU 12 pin: Firmly, over and over.
- No case, cardboard 'test bench'
- New lithium battery
- Different PSU
- 1 stick of RAM
- No GPU, No RAM, just the CPU and board.
- Flash to new BIOS using USB (incredible you can do this without powering on!) Shame it didn't help.

^ All of these things give the same result; comes on, goes off, comes on goes off, no post, no hint, no hope.

Has anybody got any ideas?

 

[alexoiu]

It might be a board issue. Can you RMA it?

 

[Mike486DX]

It's used, I have a bad feeling about getting a refund as it was from gumtree and the seller has gone silent now.

Does anybody know, if using only 1 stick of RAM, which slot to use? Does it matter?

 

[Ironsounds]

Hello... re-peat your tests... without a ext GPU... AlWAYS un-plug the PS from the WALL... to get all the MB chips to "0" condition... there is still 3.3Vdc and 5Vdc on the MB circuits unless you switch off the PS for a few minutes.

The MB battery hold the "1" & "0" in the CMOS chip... for your MB/Hardware devices... and there is capacitor, in that circuit, that gives you reasonable time to change it, and not lose or change the CMOS information. I think your Cmos information needs to be "re-created".

Let's try a proper "battery removal" AND CMOS reset Clear to the MB ...ok? B /

Take your time here and be slow and careful to your MB... look in your MB manual/Pdf for pictures and location of the SW (switch) or jumper pins. B )
1) un-plug PS from wall.
2) remove MB battery
3) place jumper pins/switch on MB to clear the capacitors... for ~3 mins
4) remove Jumper/switch
5) re-install battery
6) plug monitor into the MB video output OR Video card for a BOOT display
8) plug in PS to wall
9) Boot computer.

Get the MB hardware to the BIO's screen and report back. B )

 

[alexoiu]

It doesn't matter. Try testing each slot.

 

[Ironsounds]

Hello... a CMOS clear is required any time you move RAM to other slots B ) your MB manual PDF should have a pic and recommended slot use when using single or dual channel mode memory communications.

 

[Mike486DX]

Hello... re-peat your tests... without a ext GPU... AlWAYS un-plug the PS from the WALL... to get all the MB chips to "0" condition... there is still 3.3Vdc and 5Vdc on the MB circuits unless you switch off the PS for a few minutes.

The MB battery hold the "1" & "0" in the CMOS chip... for your MB/Hardware devices... and there is capacitor, in that circuit, that gives you reasonable time to change it, and not lose or change the CMOS information. I think your Cmos information needs to be "re-created".

Let's try a proper "battery removal" AND CMOS reset Clear to the MB ...ok? B /

Take your time here and be slow and careful to your MB... look in your MB manual/Pdf for pictures and location of the pins. B )
1) un-plug PS from wall.
2) remove MB battery
3) place jumper pins/switch on MB to clear the capacitors... for ~3 mins
4) remove Jumper/switch
5) re-install battery
6) plug monitor into the MB video output OR Video card for a BOOT display
8) plug in PS to wall
9) Boot computer.

Get the MB hardware to the BIO's screen and report back. B )

I'll try these now, thank you. No onboard graphics so the GPU will need to stay in place for now.

 

[Mike486DX]

Hello... a CMOS clear is required any time you move RAM to other slots B ) your MB manual PDF should have a pic and recommended slot use when using single or dual channel mode memory communications.

I didn't know that, surprisingly the manual doesn't seem to make mention of specific slots.

Just tested the RAM in another machine and it's fine.

 

[Ironsounds]

Hello... Great... Good test & RAM... get them in the proper MB slots and do a battery removal and CMOS clear for them to be read on the next Boot. B )

Set your Monitor for the type of cable you are using from the EXT GPU card.

 

[Mike486DX]

Hello... Great... Good test & RAM... get them in the proper MB slots and do a battery removal and CMOS clear for them to be read on the next Boot. B )

It's now unplugged with no battery ~ there's no CMOS jumper, just a button. Presumably the button still works to clear CMOS without power?

Appreciate your help, by the way. Thanks.

 

[Ironsounds]

Hello... THX... SW (switch) or jumper are now include in my instructions... old days were jumpers now they are putting switches on the MB... they both short out the memory capacitor in the circuit. B )

 

[Mike486DX]

Alas, nothing...same behaviour, brief power on then off again, a boot loop without POST.

 

[Mike486DX]

I'm starting to wonder if my CPU socket is damaged, excuse large images:

 

[alexoiu]

There are several bent pins. Try straightening them.

 

[Ironsounds]

Hello... Bootloops can mean memory/hardware is being re-read looking for a better setting to communicate... I typically clean the Ram with Q-tips and rubbing alcohol... also MULTI re-inserts into the MB can clean the slot on the MB pins.

Can you test the VIDEO card in another computer next?

Yes... bad CPU socket pins there's your PROBlem... get a maginfing glass and use a wooden toothpick to align it... and NOT break them OFF B O

 

[Mike486DX]

Thanks both, yes video card, RAM, PSU all fine with other machines.

Now going to put a flashlight in my mouth, a magnifying glass in my left hand, and a toothpick in my right. This is going to be insanely hard but I'll report back!

The guy on Gumtree said the board had never been used before but the pins were like this when it came out of the box 🙁

 

[Ironsounds]

Hello... they make headband lights... I love mine for this reason. B D
A lot of re-turned MB's will have this problem from other users... common first build errors. B O TWO pins are mis-aligned.
Ask for picture of this and/or working WEI screen when buying used.

 

[Mike486DX]

Really struggling to see what I'm doing, even with the torch and magnifying glass - I think I'll wait until daylight now, it's gone 10pm here.

 

[Mike486DX]

Here's a video I made of my endless boot loop:

https://www.youtube.com/watch?v=yEeoUEYB3d8

Note how the PSU 'clicks' upon each attempt to boot. I spent a lot of today aligning those pins and I'm starting to think they're not the problem: the board clearly recognises the CPU is in there because without a CPU, it won't even attempt to power up.

There are other people who've posted similar problems online and often with the same combination as this (P9X79 and 3930k) some have been BIOS related. Part of me wonders if something is causing a short circuit. I'm just stumped.

Flashing a new BIOS doesn't seem to have made a difference. If this really is a short, what could cause it? Where should I look?

 

[Ironsounds]

Hello... Typically I would of had a MB ordered to be delivered that night or the next day, if peoples work/$$$ was dependent this working... it is obvious the CPU socket was damaged and pre-tested and struggled with before you... and going down to Board level and traces is very time consuming, and the information out there is not 'Public" information... time is $$$ and worrying about the Little things causes wrinkles... the repair at this time is testing the CPU and ram in another "Known good" MB. B /

 

[Mike486DX]

Hello... Typically I would of had a MB ordered to be delivered that night or the next day, if peoples work/$$$ was dependent this working... it is obvious the CPU socket was damaged and pre-tested and struggled with before you... and going down to Board level and traces is very time consuming, and the information out there is not 'Public" information... time is $$$ and worrying about the Little things causes wrinkles... the repair at this time is testing the CPU and ram in another "Known good" MB. B /

I've just had an email informing me that the thread has been marked as solved.

I'm sorry, but this issues was never solved and the motherboard was thornw away. Why Ironsounds answer was chosen as being the best is absolutely beyond me.

 

[alexoiu]

Hello... Typically I would of had a MB ordered to be delivered that night or the next day, if peoples work/$$$ was dependent this working... it is obvious the CPU socket was damaged and pre-tested and struggled with before you... and going down to Board level and traces is very time consuming, and the information out there is not 'Public" information... time is $$$ and worrying about the Little things causes wrinkles... the repair at this time is testing the CPU and ram in another "Known good" MB. B /

I've just had an email informing me that the thread has been marked as solved.

I'm sorry, but this issues was never solved and the motherboard was thornw away. Why Ironsounds answer was chosen as being the best is absolutely beyond me.

It's this forum policy to have as many threads marked as "Solved", as possible.They mark old threads as "Solved", without caring too much about the content.
It doesn't help the users, but... who cares?