P67A-UD4-B3 stuck in reboot cycle

[philr]

Yesterday when I powered my computer on, instead of booting up normally it started doing the following:

• The system powers on.
• Either just one green PHASE LED or all the PHASE LEDs light up.
• After a second or so, the system powers off.
• After a few seconds, the system powers on again (without intervention).
• The system appears to POST normally. The BIOS screen is shown and one beep is heard.
• A couple of seconds after the POST beep and before the screen changes, the system powers off.
• After a few seconds (without intervention), go to step 1 and repeat.

The computer had previously been running stably for several months. I've removed all the drives and peripherals but this hasn't made any difference. All that remains connected is the following:

• Gigabyte GA-P67A-UD4-B3 Motherboard rev 1.1 flashed to F4 BIOS (originally F1)
• Corsair TX850 PSU
• Intel Core i7 2600k CPU
• 4x Corsair Vengeance 4GB PC15000 DDR3 Memory Modules
• Asus ENGGTX480 Graphics Card

It is not possible to access the BIOS configuration screen. The system still powers itself off if the Del key is pressed.

I've also tried doing the following, but nothing has helped:

• Tested each memory module individually.
• Tested a single memory module in each slot.
• Tried with no memory - the only difference to the above sequence is that instead of POSTing normally, I get continuous long beeping. The system still powers itself off after a few seconds of beeping.
• Tried a different graphics card (a much lower spec PCI-E card that doesn't require its own power supply).
• Tried with no graphics card installed - the only difference to the above sequence is that instead of POSTing normally, I get a long beep and two short beeps. The system still powers itself off a few seconds after the beeps.
• Using the CMOS_CLR jumper to reset the CMOS.
• Disconnecting the power, removing the battery and leaving the system for an hour.
• Unplugging all the PSU power connectors and shorting the power-on line to ground. When I do this the power supply switches on and remains running until I remove the power-on line short.

I'm thinking this is either a fault with the power supply or the motherboard. I am going to see if I can borrow another PSU to see if that makes any difference, but can anyone else suggest anything else to test? Is it possible for a CPU fault to be causing a problem like this?

Thanks,

Phil

[F5BJR]

*
At first time test with minimum of components and another power supply

If possible use a basic graphic card ( Low Power Consumption )

Pierre

[Dark Mantis]

Yes it is possible that it is the PSU but equally possible that it is the motherboard.

All the LEDs light up when first starting but then should go out as POST progresses.

Try updating the BIOS and then synchronising them both before loading the Optimised BIOS defaults.

[philr]

At first time test with minimum of components and another power supply

If possible use a basic graphic card ( Low Power Consumption )

I will try and test with another power supply.

I have already tried with a basic graphics card that doesn't need any extra power connectors. It made no difference - the problem still occurred exactly as it did before.

All the LEDs light up when first starting but then should go out as POST progresses.

Try updating the BIOS and then synchronising them both before loading the Optimised BIOS defaults.

None of the LEDs go out until the power switches off (at which point they all do). I can't remember what they did before the problem occurred.

I can't enter the BIOS Setup or Q-Flash utility, so I can't flash the BIOS. Pressing Del or End on the keyboard doesn't do anything - the computer just powers itself off after a few seconds (as it would have done if no key was pressed).

Thanks for your help,

Phil

[Dark Mantis]

Have you tried replacing the keyboard with a PS2 model ? If you are currently using a USB version it can sometimes cause problems like this.

[philr]

Have you tried replacing the keyboard with a PS2 model ? If you are currently using a USB version it can sometimes cause problems like this.

I've just tried a PS/2 keyboard instead of the USB one I was using earlier. It still won't go into the BIOS setup or Q-Flash though.

[Dark Mantis]

I would suggest that the next step should be a strip down and bare bones rebuild outside of the case.

Remove the motherboard from the case and test it on the workbench.

Make sure that you observe anti-static precautions.

Lay some cardboard or use the motherboard box that is non-conductive on the worktop and remove the motherboard/CPU/heatsink/fan/buzzer/one stick of memory and PSU from the case and put it on the cardboard. Add the keyboard and now I know you haven't got any graphics but try and boot. The system should try and then fail emitting a series of beeps. Please post what sounds it makes.

[philr]

I would suggest that the next step should be a strip down and bare bones rebuild outside of the case.

I've done a rebuild as you suggested. Without the graphics card plugged in it makes one long and then two short beeps and then powers itself off after a couple of seconds. With the graphics card in, it POSTs, but still powers itself off. I am still unable to get into either the BIOS setup or Q-Flash.

I've also now tested the power supply and memory in another identically specified machine. They work perfectly in the other machine, so this narrows the problem down to either the motherboard or CPU.

Finally, I've tried the instructions at http://www.tomshardware.co.uk/forum/275856-12-gigabyte-guide for breaking a boot loop (about two thirds down the page). I was unable to get into the BIOS in the 'power up' step.

I think I'm now going to have to look at getting a replacement motherboard unless anyone has any other suggestions.

Thanks,

Phil

[Dark Mantis]

Ok Phil, try this then. It will kick in the Backup BIOS instead in case the Main BIOS is corrupted.

It might take a few attempts to get right but just persevere.

You can kick in the backup BIOS by shutting down the PSU from the wall, then hold down your case power button in and then turn on the power supply button, a few seconds later the board will start, shut off the power supply then.   Then you can turn on the power supply again and power up the board normally and DualBIOS will kick in.

[philr]

Ok Phil, try this then. It will kick in the Backup BIOS instead in case the Main BIOS is corrupted.

That seems to have fixed it, thanks. After about ten attempts, a message about a BIOS corruption error appeared on screen and the recovery HPA BIOS was copied over (or something like that - I wasn't quick enough to copy down the details). After that the system rebooted itself and I was then able to get into the BIOS setup and Q-Flash. I've now flashed the main BIOS to F5 and the system is running properly again (and has managed to power on successfully a few times).

Before the problem occurred, the main BIOS was on F4 and the backup BIOS was on F1. The BIOS loading screen on the even boot cycles (the ones that made it to the POST beep) was showing version F1, so I presume that means it was using the backup BIOS at this point. Does the fact that the backup BIOS was unable to load mean that it is in some way corrupted? Would it be a good idea to flash the backup BIOS too?

Thanks again for all your help,

Phil

[Dark Mantis]

I always suggest trying the new BIOS version for a couple of weeks to make sure it is ok and there are no big bugs in it and then when you are sure you are happy with it synchronise the two BIOSes so that they both have the latest version on them.

Follow these instuction for how to accomplish that.

To check, go into the BIOS and on the MAIN page press F9 for system info.   You should see both BIOS versions listed, if they do not match please update the backup BIOS to match the current.

To do that, reboot and where you would normally press DEL to enter the BIOS, instead press Alt + F12, this will flash the Backup BIOS with the MAIN BIOS contents.   Do not worry when you see a recovery comment, that is normal and means it is flashing the backup BIOS.

[philr]

Since my last post the motherboard has got itself stuck in the same reboot cycle on two separate occasions. Both times the problem started when I went to turn the machine on. I pressed the power button and initially nothing happened. Then, after a few seconds, the backup BIOS loaded (as indicated by the lower BIOS version) and reported the following error:

The system has experienced boot failures because of overclocking or changes of voltages.

Last settings in BIOS setup may not coincide with current H/W states.

After pressing a key to continue, the system went into the reboot cycle described in the first post of this topic. The CMOS had clearly been reset or corrupted at this point because the boot logo was being shown despite having previously switched it off.

Both times I have been able to recover the system by following Dark Mantis' suggestion of holding the power button in and turning on and then off at the PSU. After doing this a few times, the system eventually shows the following message, powers off and then is able to go into the BIOS setup and boot again:

Warning: MAIN BIOS CHECKSUM ERROR!

Retrieving recovery source from HPA.... HPA BIOS not available!

Retrieving recovery source from Backup BIOS!.... Done!
Writing BIOS Image.....

Is there anything I can do to find out what is causing this issue and to prevent it happening again? Is it likely that the motherboard is faulty?

Thanks,

Phil

[Dark Mantis]

To be honest it is something that I see quite often on the forum here and have even had it happen personally. After some investigation I put it down to whatever Gigabyte uses as a trigger to decide that this has happened is far too sensitive and it throws it up on random occasions. Ususally there is no real reason for it to happen!

On most users motherboards they don't overclock anything not even the memory and yet the machine still thinks there is an overclocking problem, throws up the message and loads the Backup BIOS.

[gamefrk]

I am having a difficult time isolating the issue with my PC. I have the boot loop problem as well. I flashed my motherboard to the latest BIOS firmware (F7), and that fixed my problem temporarily. But the problem is back again. Sometimes it will power up for 15 seconds, long enough to get to the memory test (the screen that shows the memory frequency) and sometimes it will power on for 1 second and shut off for 5, and repeat that. So this is what I discovered... I have a Radeon 6970 with 4 displays attached to it (2 into the dvi ports, and 2 into the mini-display ports), when I unplug some of the displays (the 2 displayport monitors), everything boots up fine.

All my equipment ran fine for several months, but recently I've added 2 more monitors and went form 8 to 16GB ram. Now a couple weeks later, I'm having these issues.

i7-2600k
16GB G.Skill 1866
1x SSD
3x 7200 Drives
1x DVD Drive
1x XFX Radeon 6970

I'm running all this on a 750W power supply (hec Zephyr MX 750).

So this complicates things for me, I thought it was the motherboard...
Now it seems to be the power supply or the video card.

Any ideas?

[Lsdmeasap]

Is it fine on 8GB?  That could also be the issue, you may need to tweak things a bit further than what you already have to stabilize that much memory.  Or is it fine if you remove the two new monitors?

Also, please be sure you flash the backup BIOS to match the main BIOS, this is very important on P67/Z68 (As is having the latest BIOS, which you already covered).   Here's how to do that, you may need to use PS/2 keyboard or USB to PS/2 adapter
http://gigabytedaily.blogspot.com/2011/02/video-guide-how-to-update-your-backup.html