I am telling you, BOTH Crosshair IV and Crosshair Z, (i blew the Crosshair IV), have the exact same problem as TS and I described. There is nothing faulty about the harddrives. They are in good condition and run for days 24/7 perfectly doing all sorts of things.
The problem occurs when you hook up 2 or more identical, or at least a combination of SSD + HDD in pair. The HDD starts 'clicking' upon boot. This may sound to you as a hardware faillure, but it's not! The faillure is that from my experience, the drive or controller has problems properly detecting that disk.
My previous posted problem on the Crosshair IV happens also on the Crosshair Z. Brand new s-ata cables, 750W Antec PSU which drove a 2x 270x as a crossfire setup easily, and a 5GHz OC'ed 8320 CPU.
There is nothing underpowered on my system. Power feed to hardrives is balanced with 2 cables on 2 different (modulair) slots on the PSU. If you doubt that Antec is a bad brand, man i'm buying antec for years and they always performed excellent, even in crazy oc states.
I've just checked the
https://www.asus.com/Motherboards/CROSSHAIR_V_FORMULAZ/HelpDesk_Download/ page with any (and hopefully) updates, but nothing is on there. So right now i have a computer with 1 ssd, 1 1TB drive, and 4 useless HDD's which i cant properly use together. I either toss away this Asus product or buy a raid controller and use them as JBOD, which is a terrible sollution anyway if you ask me.
Again; i have the exact same problem as TS. I've experienced this on 2 premium AM3+ motherboards, both Crosshair IV & Z. You'd expect the Z to be the top notch of motherboards, they are yes in various ways, but when it comes to support of various HDD's together, you run into issues.
These are the things why i am doubting any future buy of Asus products. A HDD / SSD is a mandatory in any computer. I'm not confident to run up to 1TB of data on a disk that might go bad some day, with the risk of losing up to 1TB of data.
As a matter of fact, the link in your above post, >
http://knowledge.seagate.com/articles/en_US/FAQ/223631en suits my disks. I am going to try and give it a firmware update. I have 3x HD502HL models. When 1 is running, no problem, when 2 or more are running, clicking occurs. Sometimes pulling the power cord, and put it back in with an instant startup solves sometimes that problem.
But it's not the way i'm supposed to startup a computer at all.