PCI Express x4 network card into PCI-Express x16 slot?

GPU in PCIEX4 instead of x16 can you put a pcie x4 in a x16 slot In size, they are all x16 so will fit any pcie card no matter the size As far as bandwidth, the first 2 slots are 16 lanes from the cpu so if candy slot game If you have limited expansion slots on your motherboard and all you have available is an

candibet slot You can put smaller cards in a larger slot, but not the other way around So a 1x will fit in a 16x or 8x slot but a 8x won't fit in a 1x