Random BSOD 'hal.dll+12a3b'

Hi there,
so recently I've changed my PC set, mb to Gigabyte GA-Z97-HD3, CPU to i5-4690k, GPU to MSI GTX 970 4G.
After a week or so, random BSOD came by to say 'hello' to me.
RAM, SSD, PSU and other stuff are exactly the same as previous PC, and worked fine before changing.

Most of the time, BSOD happen' when system is working on IDLE... Never happen during gaming nor watching movie...
1. Temps are OK,
2. I did reset my CMOS setting as this CPU was OC'd to 4,4GHz (now on default).
3. RAM seems to be OK, although didn't test it in memtest 86+ yet, but as mentioned 2 weeks ago on old setup didn't notice any BSOD for a very long time.
4. Gigabyte's EasyTune was also removed.
5. All drivers are up to date, same for win7 updates.

thank you in advance for your time and help, Karol.



EDIT: Memtest 86+ passed. I did my own investigation while waiting to reply, found out ubssrv_oc_only is common failure process. Regarding to some posts (few from here) I've uninstalled iCloud app from Gigabyte.
Will update this thread if its gonna fix BSODs.

Your latest dumps are all 124 errors and these are typically related to a hardware issue and can only be isolated by stress testing the major components.

If overclocking, reset all overclocks back to their default settings and then follow these:
RAM - run for a minimum of 8 consecutive passes
RAM - Test with Memtest86+
CPU - run the HIGH test
CPU - Stress Test Using IntelBurnTest
Video - run the FURMARK test for 20mins
Graphics Card Problems - Diagnose
Video Card - Stress Test with Furmark
Storage - run the SHORT test using the DOS version
SeaTools for DOS and Windows - How to Use

Code:

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*                                                                             *
*                        Bugcheck Analysis                                    *
*                                                                             *
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Use !analyze -v to get detailed debugging information.
BugCheck 124, {0, fffffa800767f028, bf800000, 200401}
Probably caused by : GenuineIntel
Followup: MachineOwner
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