Modern motherboards with 6+ usable PCIe slots?

PCIe x16 Gen expansion backplane with two slots The PCIe x16 Gen3 backplane has two PCI Express x16 slots, with one slot supporting the OSS target

The 'x16′ indicates the maximum number of PCI Express lanes supported and thus, the length of the slot As version , each lane provides

pcie 30 x1 slot your i5-3470 works on PCIe natively, Optiplex 7010 has only one slot bound to CPU PCIe, others are linked via chipset

pcie x 16 slot Depending on your graphics card and motherboard, some of the PCI-e slots x16 lanes), but to make sure, it's worth checking your motherboard's manual