What Happens When You Fry a Motherboard?

A fried motherboard is a sign the computer you depend on for business correspondence, Web work and billings is a total loss and pretty much useful only for holding down papers. Heat is the desktop PC's enemy; excessive temperatures can destroy sensitive components in seconds. Although in some cases, a competent technician can repair a fried motherboard, you usually must buy a new PC.

The motherboard is the largest circuit board in a PC. Among many other devices, it holds the microprocessor and memory which are crucially important to the computer's operation. It also has connectors for power, the hard drive and CD/DVD drives, and peripheral component interconnect express slots for video, network and other accessory cards. The motherboard's dense network of circuit connections make physical damage very hard to repair.

The microprocessor chip is the single most important component in a PC, as it runs all your software, performing hundreds of millions of calculations per second. Running at such high speeds, the processor produces large amounts of heat, with some chips rated at over 100 watts. The microprocessor has its own cooling fan and an aluminum heat sink to carry heat away from the chip. If the fan stops working, the processor's temperature rises rapidly, burning itself up.

Overheating components such as a microprocessor can scorch the fiberglass material that makes up the motherboard. In addition, the metal foil patterns that carry electronic signals peel away from the board, destroying delicate circuit connections. High temperatures melt plastic circuit connectors and damage components such as resistors and capacitors.

The extent of damage to a fried motherboard determines if it can be repaired or not. Sometimes, only the microprocessor itself is damaged. In most cases, the microprocessor sits in a socket, allowing easy replacement if necessary. Many times, however, the board is too damaged to repair. If the computer manufacturer still offers the same motherboard, it's possible to replace it, but it may cost more than a new computer.