Hi your mini-dumps don't appear to be pointing to anything in specific but I can suggest some things that may help.
Firstly remove any gadgets you may have on your system left over from Windows 7. One of your minidumps points to:
sidebar.exe which is a sidebar gadget belonging to Win7/Vista and may not be compatible with Windows 8:
sidebar.exe Windows process - What is it?
You might also want to un-install Ultradefrag for testing purposes as another mini-dump points to the file:
ultradefrag.exe
I have noticed two drivers you will need to update on your system or un-install/remove if un-needed:
ASACPI.sys - Asus ATK0110 ACPI Utility, also a part of the Asus PCProbe and AISuite Utilities:
Driver Reference Table
The above driver is part of
ASUS AISuite Utilities and is a
known BSOD maker and therefore should be un-installed via the control panel. If you cannot find this suite in the control panel/remove program then please go into your
c:\windows\system32\drivers folder and rename the file to:
ASACPI.bak and reboot your PC.
Rt630x64.sys - Realtek PCI/PCIe Adapters:
Driver Reference Table
Part of the Realtek network interface controllers. Please select your controller and install the Windows 8 version of the driver is possible:
Realtek
Please make sure that you install all Windows 8 updates until you can install no more.
-cheers