What's the use of a 2nd PCI-E x16 slot ?

A PCIe x16 slot provides 128 GBs bandwidth, enough to support a PCIe x16 full-height half-length slots, plus 1x OCP slot Internal: For

Die Bezeichnung x1, x4, x8 und x16 sagt aus, wie viele PCIe-Lanes in dem Slot kaskadiert sind Grundsätzlich funktionieren kurze Karten auch in langen Slots

pcle x1 slot your i5-3470 works on PCIe natively, Optiplex 7010 has only one slot bound to CPU PCIe, others are linked via chipset

pcle slot x8, x16 PCIe Gen 3 bandwidth, 1 GBs, 2 GBs, 4 GBs, 8 GBs, 16 GBs PCIe Gen 4 Does PCIe Gen 4 make PCIe NVMe SSDs faster? PCIe Gen 3 was unable to