HDD Not Found When CSM Support Disabled in UEFI

[Endless Derp]

I built a computer with a Gigabyte GA - Z170X - Gaming 7 motherboard, a 120GB Kingston SSD, and a Western Digital Blue WD10EZEX OEM HDD.I have Windows 10 installed on the SSD so I'm booting with CSM support disabled; the UEFI wouldn't otherwise recognize the SSD. However, the UEFI isn't recognizing my HDD this way. Disk Management is finding the HDD and it's a healthy NTSF partition, but File Explorer isn't and I can't use it for storage as I had intended. When I enable CSM support the UEFI does find the HDD. I've tried playing with the CSM support options, but I can't find a way to have the UEFI recognize both the SDD and the HDD.

 

[Endless Derp]

I would very much appreciate someone else checking my solution, but I just fixed the problem with this:

http://www.tomshardware.com/answers/id-1662802/solved-hdd-shows-device-manager-computer.html

 

[ArtPog]

1. Given your system there's hardly any reason why the CSM should be enabled. I assume it was disabled by default, right?

2. I'm at a loss to understand the "solution" you referenced. What do you mean you desire "someone else checking (your) solution". What solution?

3. Is this simply a case where your HDD is connected as a secondary drive in your system and it is not "recognized" in the system because a drive letter hasn't been assigned to it via Disk Management? Or is the HDD not listed in Device Manager?

4. If the latter, can you install that disk in another PC either internally or externally and determine if it's detected in that system?

 

[jameswiz]

I had the same problem on a Brand New board (now is Aug2018)... I'm using a Gigabyte Z370 Aorus Gaming Ultra Wifi-OP.. The OP means the board comes with 32gb of Optane Memory Installed... When I disabled CSM Support and rebooted, The BIOS no longer showed the Optane Memory, or my SSD... After MANY MANY Hours of trying different bios options, I finally said "screw it" and booted from my Windows Install USB Drive, and found that BOTH the SSD and Optane Memory stick were showing inside the Windows Installer... I was able to install Windows 10 and Boot... The system is working as it should...
I've also emailed Gigabyte to ask if them not showing in the Bios is a setting or Glitch... I'll try to post an Update once I know...