What Should to Do With Extra PCIe Slots?

can i use m 2 pcie 4 0 in 3 0 slot   Dan can you put pcie 1x in 16x slot

Given your graphics card's specs, the max speed is 14 Gbps, which is well within the reach of what PCIe can handle They also just specify

PCIe PCIe x 16 Slots 7 · 6 · 5 · 4 · 3 · 2 · 1 SSD Slots 5 x Ultra-Fast Storage：4*PCIe x4 slots; Efficient Overall Thermal：VRM Thermal 2 x16 Gen 4 Card is compatible with the Intel® X299, Z390, Z370 and future platforms' RAID-on-CPU function, and supports PCIe NVMe RAID on the AMD TRX40 and

bali 77 slot PCIe x16, 1 PCIe x16, 1 PCIe x1, 1 Key E for WiFi; Graphics Output Options: HDMI, DisplayPort, D-Sub; AMD CrossFireX™; CH HD Audio When installed in a Windows PC's PCIe slot with four SSDs formatted in a RAID 0 configuration, the card is capable of 8,500 MBs transfers Aggregate