Thank you for contacting our support community. We understand your situation regarding the Intel® Optane™ Memory.
In order to accelerate your secondary drive you will need to meet the following requirements as per https://www.intel.com/content/www/us/en/support/articles/000027987/memory-and-storage.html this article:
As per https://www.gigabyte.com/Motherboard/Z370N-WIFI-rev-10# support-dl Gigabyte* support website, there is a BIOS update that supports the Intel® Optane™ Memory and it is F4.
We recommend you to contact https://www.intel.com/content/www/us/en/support/topics/oems.html Gigabyte* in order to confirm that the BIOS version F4 contains the Intel Optane memory-enabled motherboard with the Intel® RST Pre-OS UEFI Driver version 22.214.171.12402 or later that is required in order to accelerate the secondary drive.
Please let us know the outcome of your situation.
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