Original external components are expensive and usually proprietary and non-interchangeable; other parts are inexpensive—a power jack can cost a few dollars—but their replacement may require extensive disassembly and reassembly of the laptop by a technician. Other inexpensive but fragile parts often cannot be purchased separately from larger more expensive components. For example, the video display cable and the backlight power cable that pass through the lid hinges to connect the motherboard to the screen may eventually break from repeated opening and closing of the lid. These tiny cables usually cannot be purchased from the original manufacturer separate from the entire LCD panel, with the price of hundreds of dollars, although for popular models an aftermarket in pulled parts generally exists. The repair costs of a failed motherboard or LCD panel often exceeds the value of a used laptop. Parts can also be ordered from third party vendors.