View Full Version : CPU PCIe config and M.2_2

04-24-2021, 04:08 AM
I have a ROG STRIX Z590-E Gaming Series, with WiFi 6E motherboard and I am trying to utilize the M.2_2 hard drive slot. In order for the system to recognize the hard drive I have to go into BIOS and advanced>onboard device configuration>CPU PCIE Configuration Mode and change it to "PCIEx16_1 + PCIEx16_2 + M.2_2"

My question is am I choking the PCI lanes for the graphics card by doing this? I have 3 SSDs in this tower (not utilizing M.2_1) but I could easily remove one drive if it means I am indeed splitting the PCI lanes between the hard drive and my graphics card.

Other info that may be of use:
CPU: Intel Core i9 10850K
SSD in slot M.2_2: SAMSUNG 980 PRO M.2 2280 1TB PCI-Express Gen 4.0 x4, NVMe 1.3
M.2_3 SSD:1TB Intel 660P M.2
M.2_4 SSD: ADATA XPG SX8200 Pro 2TB Gen3x4 PCIe M.2 2280

The intel is the one with the boot system on it and the one that came with the rig (yes i bought prebuilt :( only way to get a 3080 these days), but i could easily make the samsung the boot drive and the ADATA my gaming drive.

04-24-2021, 10:07 AM
M.2_2 for some reason shares lanes with the CPU. So if you populate M.2_2 it will run the PCIEX16_1 slot in 8x. If you dig through the manual it will state this. I don't really understand why Asus have chose to have the M.2_2 sharing lanes with the CPU and not the chipset though...