Possible Duplicate:
Does a x4 PCIe mechanical work in a x16 slot in x4 mode?
I know I can place a smaller card in a larger slot. But can I be 100% certain that it works? (if we ignore a broken card or broken slot)
Possible Duplicate:
Does a x4 PCIe mechanical work in a x16 slot in x4 mode?
I know I can place a smaller card in a larger slot. But can I be 100% certain that it works? (if we ignore a broken card or broken slot)
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. See Wikipedia for more details.