Independent Hardware Vendor

Company that manufactures hardware components to be used on systems manufactured or assembled by other companies. Customers of IHV companies are called OEM.

So real examples. Eurone and Amptron buy motherboards from ECS/PCChips and sell them using their own brand. In this case, Eurone and Amptron called OEM, while the original manufacturer, ECS/PCChips, is called IHV.