Because that is the "official" memory spec for JEDEC at that time. When you change it to what the module can do, that's called a XMP profile for Intel.Yes it's an Asrock Z170.
I'm curious why Auto would set it lower...
It shows that the module IS RUNNING at JEDEC speeds, not XMP.The CPU-Z shot is showing the module's JEDEC default (2133 CAS 15).
Not on ASRock boards, in my experience, at least, not their Z170 boards. Mine required setting XMP "Enabled" AND setting the DRAM clock appropriately, and maybe even the voltage. Weird, I know. Most boards, when you set the XMP profile, the DRAM clock and voltage (and timings and sub-timings) all get set automagically (along with MCE on some boards). Not on ASRock.The motherboard shot shows you have loaded the XMP profile, and it running at DDR4 2800 CAS 16)].
I just tried it on PC, and you're right. It shows the higher speed my RAM is running at (but the version the OP is using appears to be an older build). The version I have is 1.89.1, and I've had this version for a while now.It shows that the module IS RUNNING at JEDEC speeds, not XMP.