My ASRock Z77 Extreme 4 is unreliable

[idk846]

It takes 3-7 attempts to successfully boot my machine. It is a gamble to put it in sleep mode as well. I strongly suspect it is because of the Mobo or CPU. See note 1 for excessive details.

This problem has persisted for at least a year now. I've avoided it by never turning the machine off or letting it go into sleep mode. It was only tonight where the number of times I had to re-power my machine was far higher than normal (~30 times I am guessing). The solutions I have found through Google have not worked. None of them describe a problem exactly as the one I am having.

So far I have:

• 
  Attempted to boot using 0, 1, and 2 sticks of RAM using slots B1 and A1 as well as B2 and A1
  Cleared CMOS several times using the smart button
  Cleared CMOS by removing the battery for 10 minutes
  Re-seated the CPU in order to check for bent pins
  Checked all the standoffs were correctly tightened. See note 2 for excessive details.
  Unplugged and replugged the wires which power the mobo
  *NEW* Updated the BIOS from 2.2 to 2.9

It is currently running right now. I think this is independent of the attempts at a solution listed above. Here are three things that may be relevant to this problem.

• 
  I may have damaged something physically. I think this problem began after I switched computer cases and the PSU. I say I think because I have left the problem as it is for about a year now so I am not positive about this. My concern is that I may have damaged the hardware during the transfer. The PSU has been replaced so this seems unlikely to be the answer.
  I may have damaged something internally. I had overclocked my CPU in the past. I was still receiving a BSoD during lengthier periods of heavier game play so I decided to revert the process until I had a firmer grasp of OCing. I did so by loading the UEFI defaults in the setup screen at start up.
  The BIOS may be corrupt. [strike]I had updated my BIOS in the past from 2.0 to 2.2. This was the first time I had ever done that. I believe I did it through windows. I cannot say with certainly if the problem started occurring after that, but my gut says no.[/strike] I have recently gone from 2.2 to 2.9 for the BIOS. The installation did reset during the install but I managed to get back into the BIOS after many resets and install the new BIOS properly. Even afterwards I still was not able to boot until after many hours of re-powering the machine. During the boot sequence a message appeared that said something about "ME error" and then "after POST." I did not get the message quick enough before Windows booted normally.
  *NEW*Something is wrong with the power flow to the CPU. I am not sure where though. It could be in the PSU, the CPU, or the wires that connect them. The LED lights for the "Clear CMOS" button in the back and the smart power and reset button are not lit up even when properly booted.

The parts in my rig are as follows:

• 
  CPU: i5-2500k with a Noctua NHD-14
  Motherboard: ASRock z77 Extreme 4
  GPU: EVGA GTX 670 FTW
  PSU: Corsair RM750
  RAM: 2x4GB Crucial Ballistix Sport DDR3 1600
  OS: Windows 7

NOTES:

• 
  1 - In order to power the machine on I have to open the side of the machine to see the LED for Dr. Debug. If there is no LED display I reset the CMOS with the PSU unplugged. If there is, I have to see if Dr. Debug displays '00'. If it does I then have to re-power the machine by holding down the smart power button. Until today, this had to be repeated 3-7 times before I would successfully boot to windows. The wired button will work but as I am facing the side of the machine watching the read out I find it easier to use the smart button.
  
  2 - My version of tightened on a motherboard means to turn the screwdriver while pressing down with only my index finger. I then turn the screwdriver until the screw is secure enough to resist the torque of the screwdriver and it slips out of the head. I bring this up because I have read issues about over tightening with no established standard of what 'too tight' means.

 

[iam2thecrowe]

have you updated the BIOS to the current latest?
Sonce the problem likely ocurred after you swapped the PSU, this likely the cause and the problem description also points to PSU. I know it was new, but that doesnt mean its not faulty. I've also seen a few cases where a particular PSU just doesnt play nice with a particular setup, yet works fine in another setup.

 

[idk846]

have you updated the BIOS to the current latest? ...likely the cause and the problem description also points to PSU.

I have not yet done this as I wanted to post this first. I am uncertain if I should flash from a USB or windows. I would think from a USB drive would be safer.

I mentioned I replaced the PSU after the problem began occurring. The order of events for the PSU was: Old PSU --> New PSU ---> Copy of new PSU. I am not sure if I worded it well enough after rereading it. Does this change your opinion about the PSU being the problem?

 

[idk846]

I am attempting to flash to BIOS now through a USB stick. I now have the problem where the process resets the computer. I then stall out at '00' again. I am now unable to get the computer properly booted again.

 

[iam2thecrowe]

updating the bios with the windows util is fine. I cant rememver how i did it last time, i think i did use a usb and then went in bios and flashed from there. I thought "00" means its booted ok? ill check what mine says when i get home.
Try take the vid card out and plug the monitor into onboard video see if you get a display. I had an issue with mine originally with blank display and had to boot with onboard first, then install my vid card, then reboot and connect monitor to vid card.

 

[idk846]

I have tried booting with as few things as possible plugged into the motherboard and every combination thereof. It makes no difference. I seem to have an entirely random chance of getting the machine to boot regardless of what I do. That chance is always very low.

 

[idk846]

During these past few hours I have finally managed to update the BIOS. I have yet to be able to boot properly. Every error code has been '00.' I will post if I can get anything different.

 

[idk846]

I have finally made it into windows but I still have no idea why my computer will only post 10% of the time I turn it on.

During the boot, some message came up that said something about an "ME" code I think. Then it displayed another message that ended with the words "after POST." I did not read them quick enough to memorize them.

I still am not sure if this problem is resolved. Even after updating the BIOS the machine had way too much trouble properly booting.

I would also like to mention that the CPU fans do not turn on when I try to boot whereas everything else does. When I am able to boot, the CPU fans work fine. However, the lights on the MOBO are not lit up. That is to say, the "clear CMOS" light on the back panel is not let and the power and reset next to Dr. Debug are not lit.

 

[iam2thecrowe]

I would try another PSU if you have a spare. It could still be a faulty motherboard though.
After bios updates you should always load defaults, from exit menu, load uefi defaults. save and exit.
I have checked my bios, make sure under Boot menu, fastboot and fullscreen logo disabled. boot failure guard enabled.
If your really keen, if you turn on the pc and it doesnt boot, no cpu fans spin or whatever, get out your multimeter (assuming you have one) and start measuring the voltage from the 24 pin motherboard connector. If no fans spin i'd say its not getting 12v.

^ here has a good reference of voltage for different connectors/pins.
http://www.overclockers.com/forums/showthread.php/501063-Case-CPU-Fan-Voltage-Specs <source

 

[idk846]

I would try another PSU if you have a spare....
If your really keen, if you turn on the pc and it doesnt boot, no cpu fans spin or whatever, get out your multimeter (assuming you have one) and start measuring the voltage from the 24 pin motherboard connector. If no fans spin i'd say its not getting 12v.

The only reason I have not tried a new PSU recently is because this is the 3rd one I am on over the course of 2 years. The problem has always been there. It has just gotten far worse recently. I was certain that 750W was enough head room given my set up as it was adequate enough to run the machine for days when I had it OCed and two GPUs in it.

The other idea seems great. I am just reluctant to do it until I can spare the hours it takes to get the thing to boot again. Once I power it off it is a lengthy process to get it back up again now. I would love to test it the BIOS update resolved the issue or if I can replicate the "after POST" error again but I don't want to risk losing another 2-4 hours just getting back up again at this point in time. Once I get past certain deadlines I will attempt your solutions. I'll just have to find a multimeter first!

If the Multimeter does tell us something, would that mean I need to replace the PSU?

And just to be clear, it is only the CPU and switch lights that do not seem to be powering on. The hard drive starts spinning, the optical drive can be heard, the USB ports send out power (I think; I left a phone plugged in to test this), all other fans turn on, and the LED for Dr. Debug all function normally.

Sidebar: Is there a way to test for damage to the CPU or any of the mobo capacitors?

 

[idk846]

I would try another PSU if you have a spare. It could still be a faulty motherboard though.
After bios updates you should always load defaults, from exit menu, load uefi defaults. save and exit.
I have checked my bios, make sure under Boot menu, fastboot and fullscreen logo disabled. boot failure guard enabled.
If your really keen, if you turn on the pc and it doesnt boot, no cpu fans spin or whatever, get out your multimeter (assuming you have one) and start measuring the voltage from the 24 pin motherboard connector. If no fans spin i'd say its not getting 12v.

^ here has a good reference of voltage for different connectors/pins.
http://www.overclockers.com/forums/showthread.php/501063-Case-CPU-Fan-Voltage-Specs <source

I have finally gotten around to testing my machine.

I have not obtained a multimeter since we last spoke.

I have tried a different PSU with nothing but the CPU and heatsink attached. This still gave me the same results I was already getting. Boots are still random and sporadic.

Because of this, I do not think the problem lies with the PSU but instead with the MOBO. However, I cannot say where or why. I did not test this problem in time to make a trip to microcenter, but I'll pick up a new mobo when I get the chance to test that.