Can I be 100% certain that a PCIe x4 card will fit in a PCIe x16 slot?

PCI Express x4 slot running at x1 pcie x4 in x16 slot The second PCIe16 slot is an electrical x4 slot wired to the chipset In theory, both x1 and x4 should support up to 25W (x16 slots support a pcie slot for gpu Install a PCI Express x16 card into a PCI Express x4 slot, in a 1U chassis The PEX4TO16R PCI Express x4 to x16 Slot Extension Adapter lets you install PCI

pcie 4 slot PCIe is the component connection port used by motherboards The newest standard is PCIe and with x1, x4, x8, and x16 slots Many motherboards have