BSOD during sleep mode ntoskrnl.exe (nt+0x8207A)

Welcome aboard.

Code:

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*                        Bugcheck Analysis                                    *
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Use !analyze -v to get detailed debugging information.

BugCheck 1000009F, {4, 258, fffffa8007338040, fffff80000b9c3d0}

*** WARNING: Unable to verify timestamp for win32k.sys
*** ERROR: Module load completed but symbols could not be loaded for win32k.sys
Probably caused by : memory_corruption

Followup: memory_corruption
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As all the dumps indicating the same thing, We may go for some memory test.
RAM - Test with Memtest86+

At the same time, let us enable driver verifier.
Driver Verifier - Enable and Disable

► Update the following drivers.

• Realtek High Definition Audio : Driver Reference Table - RTKVHD64.sys
• Bluetooth Audio : Driver Reference Table - btmaud.sys
• AMD Radeon(TM) HD 6630M : Driver Reference Table - atikmpag.sys

► Please get rid of these programs. Those are not any good, but problems actually.

• Auslogics Boot Soeed. Not needed at all.
• McAfee : replace by Microsoft Security Essentials - Free Antivirus for Windows
• K Lite Codec packs : Replace by Shark007's FREE Codec solutions - Windows 7 codecs
• Quick Time :Replace by Free-Codecs.com | QuickTime Alternative 3.2.2
  

Let us know how these went.

This is your network adapter driver.

Code:

Name    [00000018] Realtek PCIe GBE Family Controller
Adapter Type    Ethernet 802.3
Driver    c:\windows\system32\drivers\rt64win7.sys (7.40.126.2011, 415.10 KB (425,064 bytes), 29/12/2011 2:49 AM)

upgrade the network driver:

Download the network card driver from manufactuer's website, Realtek
Then reinstall the driver:

1. Click the Start Button, type "devmgmt.msc" (without quotation marks) in the Start Menu Search box and press Enter.
2. Double click to expand "Network adaptors".
3. Right click your network card and click Uninstall.
4. Check "Delete driver software for this device" check box, click OK.
5. Restart the computer

If windows does not auto configure the appropriate drivers at startup, install the downloaded one manually.

Update MSE regularly, too.

Your crash dumps are not showing any finite probable cause. In such a situation, it is better to enable Driver Verifier to monitor the drivers.

Driver Verifier - Enable and Disable

Run Driver Verifier for 24 hours or the occurrence of the next crash, whichever is earlier.

Let us know the results, with the subsequent crash dumps, if any.