Hey hey hey everybodeeey!
I'm new in here, I just joined to the comunity just to tell you how to fix this bad and annoying problem cuz I used to have the goddamned same one and I was like OHHHHH COME ON WTF?!!
MAKE SURE you have your 8Pin ATX CPU connected also de 4Pin, I mean, you should better have the 8 and 4 pin ATX CPU connected to your motherboard because that stabilizes better your whole system!
It's very simple, you just have to enter here: http://www.asus.com/Motherboards/CROSSHAIR_V_FORMULAZ/#... and clic on Driver & Tools, then download the BIOS 1901 to an empty pendrive, rename the file to C5FZ.CAP and plug it to the only white USB port back in the back of your towercase with the system turnt-off (IMG OF THAT WHITE USB PORT: http://rog.asus.com/wp-content/uploads/2012/08/crosshai...), turn turn on your PC, press F2 and DEL repeatedly like you were dying xD load the optimised default settings and reboot again. After that go to TOOL and clic on ASUS EZ Flash Z Utility, next select the USB device that contains the BIOS data and press ENTER and OK and wait just a lil bit til the system installs the new BIOS. Do you want to read this file? Hell yeah, you do! Do you really want to update? Yes, you do too.
After the reboot you may have an Error Message: "CPU Fan Error!" Do you know what? It doesn't matter, just don't play attention to that messege, just press F1.
NOTE 1: If you still having post problems it may be the DRAM Voltage, check how many voltage do your RAMS Sticks needs and set it on the BIOS at Extreme Tweaker almost at the end of the list.
Note 2: If you still having CPU Fan Error! go to BIOS>Monitor>Fan Speed Monitor>CPU Fan Speed>and set it to IGNORE. You may say why? Simple, if you have watercooling the Motherboard doesn't recognize it at the booting.
And that's all guys, wish you good luck
Tyrakz.-