Is 7010's PCIe x16 slot only Gen ? Can I upgrade to ?

can i put pcie x4 in x16 slot   Dan candy bar slot

According to PCIE Expresscard , a x1 card can be inserted into the x4, x8, and x16 connectors 15 This is referred to as up

Yes, a PCIe x4 card will function in a PCIe x16 slot The slot will simply use 4 of the 16 lanes available, and the card will work properly  There's been talk that some PCIe slots on new motherboards will (The support may only be extended to ordinary PCIe x16 expansion slots

queen of wands slot If the PCIe slot has x16 mechanical and x8 electrical, you can have 16 cards, but performance gets halved due to half the lanes That is how you can fit a PCIe Physically yes, the slot connector for an x4 is generally smaller and PCIe is designed that smaller cards can occupy larger slots if needed