ASUS P8Z77-V Premium Review: A Bentley Among Motherboards

ASUS P8Z77-V Premium In The Box

Being ASUS’ top channel SKU, bonuses in the box are expected to be numerous and beneficial – perhaps even better than the package supplied by the P8Z77-V Deluxe.  ASUS definitely do deliver:

IO Shield
Driver CD
User Guide
WiFi User Guide
Six SATA Cables
2-way SLI Flexi-Bridge
3-way SLI Rigid Bridge
4-way SLI Rigid Bridge
Two magnetic WiFi antenna
WiFi Go! Card
USB 3.0 Front Box
Q-Connectors

That is a lot of extra in the box.  The WiFi module should be installed before the CPU is installed due to the way it screws into the motherboard, and the antennas are designed to magnetize to the outside of the PC case.  The USB 3.0 front box is a great addition, one that should be included in most non-mITX packages, and as expected we get several SLI bridges in what is a multi-GPU focused motherboard.

Voltage Readings

After my first publication of OCCT voltage readings, a few readers responded with a more in-depth reasoning behind some of the results we were seeing.  With this in mind, I would like to re-describe what we are doing with this test, and how it comes about.

Much of what an enthusiast overclocker does is monitor CPU temperature and voltage.  Whatever settings a user places in the BIOS or OS is at the mercy of the motherboard - in terms of actually setting the values and reporting the values back.   As an enthusiast, we have to rely on what readings we get back, and hope that motherboard manufacturers are being honest with their readings.

Take CPU voltage.  What we as a user see in CPU-Z or OCCT is a time-averaged value that hides voltage ripple (if any) for power delivery.  It is very easy for a motherboard manufacturer to hide this value, or to disregard slight deviations and report a constant value to the user.  The CPU voltage reading can be taken at a variety of places on the power plane, which can vary between motherboards and manufacturers, meaning that each reading is essentially not comparable with the other.  Nevertheless, as an enthusiast, we will constantly compare value A with value B. 

Whether or not I can achieve 4.7 GHz with 1.175 volts on a particular board is inconsequential - your motherboard may perhaps produce the same result with a reading at 1.200 volts.  The only way to test the actual value is with consistent methodology is via an oscilloscope connected to similar points on each board.  This may sound like taking an OCCT reading is therefore redundant.

However, motherboards have settings relating to load line calibration.  As load is applied to the CPU, the voltage across the processor decreases (VDroop).  Load Line calibration essentially attempts to control this level of droop, by increasing voltage when voltage drops are detected away from a fixed value.  Manufacturers have different ideas on how to modify LLC with respect to load, or whether the level of modification should be controlled by the user.  Some manufacturers offer the option at a variety of levels, such that overclockers can be sure of the applied setting (even if it increases peak voltage, as explained by AnandTech in 2007).

By doing a full load OCCT test, we are essentially determining both how aggressive the motherboard is reporting the CPU voltage under load and how aggressive load line calibration is performing (from the point of view of the user without an oscilloscope or DVM).  If someone has one of the motherboards we have tested and you have a different one, variations in load voltage should describe the offset you may require for overclock comparisons.