ASUS ROG Crosshair V Formula-Z (990FX) Review ft. Vishera FX-8350 on Phase Change
The first thing any self-respecting enthusiast should do is to load the "Extreme OC Profile", which sets optimal values all the PWM controls and turns off anything that will inhibit the overclock. Usually the only voltages you need to touch are the CPU, CPU-NB and DRAM. Everything else can be left at Auto.
This is the sub-menu for the PWM controller parameters. To prevent heavy vdroop or overshoot, ASUS recommends you set the CPU LLC to High for typical air/water and Ultra High for subzero overclocking.
The DRAM configuration is also very comprehensive, with the capability to modify primary and secondary timings as well as the expert drive strength settings. We hope the ROG team will add more memory profiles for the other memory chip manufacturers like Hynix, Samsung and BBSE. The BIOS does come with XMP support so your favourite Intel certified rams should work here, although you might need to raise the default 200MHz base clock as the memory frequency multiplier tops out at 2400MHz.
Behind the Advanced tab, you will find a CPU Configuration menu that is also very important – you will want to disable everything here except HPC Mode to prevent unpredictable throttling and clock fluctuations.
Some enthusiasts like to selectively turn off some cores here to get more ambitious clock speeds.
When paired with the elusive ThunderboltEX expansion card, the C5F-Z joins the handful of high speed Thunderbolt enabled motherboards and devices. At time of writing, neither the board nor the expansion card is certified by the Thunderbolt standards body yet, which is rumored to have implications for Windows 8 support.