pcie 4 nvme in pcie 3 slot: HP Workstation Z8G4 (13). Best Intel Z690 motherboards in 2024. How to Check Available RAM Slots in Windows 11 - GeeksforGeeks.
1TB M.2 2280 PCIe NVMe TLC SSD; Integrated: Intel I219-LM PCIe GbE and Intel X722 PCIe GbE;
Slots: 2 PCIe x4; 3 PCIe x8; 4 PCIe x16; Storage: (4) internal 2.5 ...
the third
slot is controlled by the Z690 chipset. It supports the PCIe NVMe SSDs but the allocated 4 PCIe lanes are from PCIe 3.0.
Some NVMe SSDs in add-in card form can also be installed directly into a PCIe
expansion slot on a motherboard. These cards are often referred to as "NVMe SSD add-in cards" or "NVMe PCIe expansion cards.".