DZ77RE-75K randomly restarts by itself

Hi,

I have the following problem with a DZ77RE-75K / 3770K CPU. The system will restart randomly in any delay between 1 hour and 10 days. I have this problem since I got the board with BIOS less than 61.

In BIOS 61, the fix list includes this item:

Fixed issue where computer powers down with certain graphics card and USB front panel card reader installed.

I was hoping this would be my problem (I have an nvidia GTX 670 and USB front panel SD card reader), but no. After upgrade to 61, and then 63, I still have it.

This is not a Windows software issue. Windows event log doesn't list any bug or crash as it would if there was a driver issue. Instead, I only have the following events generated after the computer restarts. It says: "system was restarted without having been normally shut down. This can happen in case of power failure"

However, my BIOS is set to keep the system off in case of power failure, and what happens is the computer simply restarts. Therefore, I don't believe this is a power supply problem, or the system would just power off and stay off. My conviction today is that only BIOS is able to restart the system in this way.

See below the frequency of occurence of the problem. The computer is always on during day, and put to sleep at night. It happened 17 times in the last 3 months. Not often, but pretty frustrating to work and know the system can fail any time, or not.

So, Intel support, what do you have say about that?

Windows event log:

Critique    07/04/2013 09:38:55    Kernel-Power    41    (63)

Critique    06/04/2013 21:46:59    Kernel-Power    41    (63)

Critique    01/04/2013 22:10:37    Kernel-Power    41    (63)

Critique    23/03/2013 13:52:04    Kernel-Power    41    (63)

Critique    21/03/2013 23:30:53    Kernel-Power    41    (63)

Critique    16/03/2013 13:36:00    Kernel-Power    41    (63)

Critique    12/03/2013 08:04:19    Kernel-Power    41    (63)

Critique    08/03/2013 18:57:57    Kernel-Power    41    (63)

Critique    28/02/2013 21:16:33    Kernel-Power    41    (63)

Critique    27/02/2013 08:33:14    Kernel-Power    41    (63)

Critique    24/02/2013 12:44:52    Kernel-Power    41    (63)

Critique    23/02/2013 19:18:45    Kernel-Power    41    (63)

Critique    03/02/2013 08:09:36    Kernel-Power    41    (63)

Critique    29/01/2013 00:00:54    Kernel-Power    41    (63)

Critique    21/01/2013 08:43:19    Kernel-Power    41    (63)

Critique    19/01/2013 12:21:23    Kernel-Power    41    (63)

Critique    16/01/2013 07:13:57    Kernel-Power    41    (63)

Eric