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Crosshair V code 66 - Posting, bios distorted?

Level 7
TL;DR: PC posts perfect splash screen, and perfect screen telling me that I need to insert media (as no OS installed), but BIOS is posting goofy with code 66 (see picture below).

UPDATE 3: Noticing the BIOS could still be adjusted, I manually set the RAM speed to 2400MHz and rebooted. Settings held. Inserted RAM back into A2 and B2, mobo recognized both sticks at 2400MHz. Currently going for broke, I decided to attempt to install an OS. So far: NO ISSUES. Mobo is showing code AA (quick searching shows this means the mobo is happy? I'll read some more as the OS installs). Basically thinking I can attempt some type of backdoor nonsense... If windows boots, and runs, I'll stress the board a bit with Memtest or some other benchmarking software.


Greetings Everyone. Longtime Asus owner, First time posting (first issue I've had!)

Building a new desktop system and I've come across a strange issue.

The system posts. And the boot screen posts just fine, along with the message about inserting bootable media (as I have no OS installed yet). It posted perfect until about 2 hours ago, when the code 66 appeared on the mobo, along with an issue booting into the BIOS. The BIOS appears to be glitching in some form or fashion. All bios values will save and be recalled if saved and rebooted. I notice Memory Clockspeed is now sitting at 1333MHz instead of the 2400MHz (due to auto). All power cables are connected to the mobo (including the 8pin and 4pin for CPU).

What I've tried so far (in no particular order):

-Soft CMOS reset via button on rear IO panel
-Hard CMOS reset via removing battery from Mobo
-removed RAM
-placed RAM in different configurations (2x in slots A2 and B2, 1x in A2, 1x in B2, 1x in all slots) with no change

This appeared to happen after I connected the front panel switches / USB 3.0 and 2.0 / audio to the motherboard, and then putting the case back together. I am unsure if this cause something to be touching the motherboard and cause a short. I have since removed the front panel connections to no avail. Next step is remove everything from the case and start fresh outside.

System Specs:

CPU: AMD FX 8370
MB: Asus Crosshair V Formula-Z (BIOS 2201 last 4 on board)
RAM: Corsair Vengeance 16GB (2x 8GB) @ 2400MHz
VGA: Gigabyte R9 390
PSU: EVGA Supernova 850 B2
HDD: Samsung 500GB SSD

Looking for any input that anyone can think of.


UPDATE 1: Removed Mobo from case to eliminate shorts. Ran into issue of only a quick flash of post screen, then black.

UPDATE 2: Issue from Update 1 was because no ROM drive or bootable attached to motherboard. Upon reconnecting my DVD drive, it went back to posting the distorted BIOS. Still have the error code 66 and RAM still booting at 1333MHz.

Level 7
I'd start by disconnecting the front panel, and making sure the stand offs are all being used, and, nothing on the back of the mobo is
touching it in any way. Error code 66 is normal until OS is booting with this board.

Read most of your post, but not sure if you installed the OS yet or not. Anyway, that shouldn't matter where the code 66 comes into play. Code 66 is
normal, until Windows begins to load, and then you should get a code AA. I'm not sure if your trying to allow the bios defaults to run, or, you plan on
setting mem speed, timings, CPU clocks, voltage, etc. There's a lot to go over before the system can be considered "stable", even at CPU/mem/etc
defaults. To me, this bios image is normal for not having the preliminary settings of choice, such as AI Overclocking Tuner (which I never use, so I set it
to disabled), CPU level up has no choice showing on it, CPU Ratio isn't set, Turbo all looks like it just came out of the box and nothing has
been done in the way of personal settings.

Set your initial specs in the bios to sure to use memory freq suggested, or, take it down to 1333, and begin a slow move towards the spee
intended for your memory. Use SPD's on the memory, set CPU to Auto, disable CPU Level Up, set AMD Turbo Core to Auto, HT and NB/HT to Auto.

Here are some desktop screens of my voltages, but remember, no two boards are the same, no two CPU's, set's of memory, PLUS, this system has a
Fair water cooling system on it, so CPU voltages should be handled carefully, and DO NOT unlock Extreme Over Volting when the CPU voltage is set to
manual. Set memory voltage (if memory is set to stock speed and SPD's) to the correct voltage + 1 increment above for stability. Also set the VDDA
1 step up for the same reason.

Remember, the settings I'm suggesting you start with should be "STOCK" on everything, until you have your OS installed and updated completely.

From where you are according to the picture of your bios, nothing has been set up yet, so if I've wasted your time with this info, I apologize.
Here are my desktop screens that will give you an idea of "my" settings, so that you can get a basic idea of what to look for, and how to get started..;
just don't try it at that speed unless you have some decent water cooling at minimum, and I advice against attempting to install the OS at speeds such
as what I am running, as it can cause problems, and possibly not be able to set up the OS at all. Also, don't hang out in the bios too
if you don't have good cooling...CPU is active and running about 5-10%, so it does build up heat.

I hope that this has been of some help. These CVFZ boards are a tad on the....well, I've had to have mine replaced twice in 1 year, if
gives you an idea of what I mean. Good board when it runs, but when it doesn't.....



Crosshair V Formula-Z/AMD FX-8350 Black Vishera @ 4.6Ghz/G.SKILL Trident X Series 16GB (2X8GB)-2400Mhz/Twin SAPPHIRE Radeon R9 270X 4GB 256-Bit GDDR5 @ 1100-1450 clocks/Twin Crucial M550 128Gb SSD's-1 WD Se WD 1TB 128MB Cache-3.5" Enterprise Hard Drive/CORSAIR Hydro Series H100i Extreme Water Cooling-push/pull 4 X 120mmFans/RAIDMAX RX-1000AE SLI Certified 80 PLUS GOLD-Modular PSU/2 X ASUS Blu-ray Burners/Asus LED VE278H/Cooler Master HAF 932 Advanced W-Fan Mods