PC reboots after exiting sleep mode

[Tine]

Hi,

I have recently noticed strange behaviour from my PC. Every time I try to wake it up from sleep state, the lights turn on and fans start to spin, but a moment later lights go off and fans stop. Then after second or two lights and fans start again and PC boots giving me error that the system was not shutdown properly.

 

At first I thought that this must be issue due to recent windows update but then I have noticed same problem when booting up PC after shutting it down manualy.

Basically every time I turn my PC ON the lights and fans turn on for a short time, then go off, and then after second or two on again and then PC boots to windows without any further problems.

 

I have striped my PC down to only MOBO, CPU and PSU (no RAM) and this behaviour after pressing power button remains (fans start to spin, than stop, then start again and remain spinning). I have also tried PSU from other PC and issue remains. I have also updated BIOS on my motherboard and load optimised defaults.

 

My PC configuration:

Intel i7-2600k (no overclock)

Asus P8Z77-M motherboard

Antec EarthWatts 380W PSU (80+ bronze)

Corsair Vengeance 2x 4GB DDR3 1600MHz RAM

Intel 520 Series 120GB SSD

Asus Radeon HD 6570

 

I haven't installed any new hardware to my PC recently. The only new thing I started doing on my PC few days before this issue emerged was playing around with Arduino software and cheap ESP8266 module connected to my PC via USB to serial converter but I don't see how that could be the reason for this problem.

 

What do you think is causing this issue (I have a feeling that something is wrong with MOBO but I am not sure) and is there anything that I could fix without buying any new hardware?

 

Any help or advice will be appreciated.

Thanks!

 

[tt2468]

There is possibility that the system hangs on suspend and then eventually crashes with 9F.  Check your %SystemRoot%\Minidump folder to see if there is a memory.dmp file. If there is, then we have a software issue.

EDIT: Another possibility is that something is going wrong with hybrid sleep. Try these steps - 

1) Search for "CMD"
2) Right click "CMD" and "Run as Administrator"
3) In the command line, type in "powercfg.exe /hibernate off"
 

[Tine]

Thanks for suggestion but my Windows\Minidump folder is empty.

[Tine]

I disabled windows hybernation mode the day I installed them. I don't think this is windows related problem because as I described in my first post this issue happens even if I turn my pc on from off state(it happens even beforeMOBO POST so way before windows even starts)

[Tine]

Update to my issue:

 

One week after this issue with my PC started it went away by itself. I do not know why but my pc now starts normally and even resume from sleep state without any issue.

 

My only guess is that something on MOBO is slowly dieing.