What Happens When You Install a CPU on Laptop Wrong?

By Andrew Aarons

The pins on the base of a CPU are delicate.
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Do-it-yourself computer repair comes with very few risks. It’s hard, if not impossible, to put a computer together wrong -- most parts only fit one way and if you can’t get a part to connect to another part the computer won’t turn on. The same is true if you decide to repair or install a CPU in one of the laptops in your office; if you get it wrong, you can just try again. The computer won’t start without a CPU, but it’s very unlikely you can do permanent damage to the computer.

Correctly Installing a CPU

The good news is that there’s really only one way to install a CPU. Most CPUs have a specific number of pins and the motherboard has a number of holes for those pins. If the CPU is turned the wrong way, you won’t be able to insert it into the motherboard unless you use a lot of force. That could cause problems (more on that later), but it’s unlikely. Line up the corner of the CPU with an arrow to the arrow on the motherboard’s CPU socket. The CPU should drop into place without any pressure at all. The pins on the CPU correspond directly to the sockets in the motherboard; if the CPU is turned the wrong way, it won’t drop into place.

Bent Pins

The hundreds of pins on the base of the CPU are easily damaged if you apply undue force. In some instances, it’s possible that you could bend and damage the pins on the CPU while forcing it into place. This will damage the CPU, but it shouldn’t hurt the motherboard unless you push so hard that the motherboard itself cracks. When the pins on the CPU are bent or missing, you’ll need to replace it. If any of the pins come dislodged in the sockets as a result of the force, you may have to replace the motherboard.

CPU Not Firmly in Place

If you line the CPU up correctly with the sockets, there’s still the slight chance that the pins won’t make contact with the motherboard because the CPU isn’t completely inserted into place. It’s okay to push gently on the top of the CPU while installing it. Most laptop motherboards don’t have the clasp mechanism found on desktop PCs that levers the CPU into place; instead, most have a metal brackets that fold down over the corners to keep the CPU in place. If the CPU is not fully seated on the motherboard, your computer won’t start.

POST Codes

When you power up your computer it performs a series of tests called the power-on self test. All computer manufacturer’s program their computers to emit beeps when certain conditions of the POST test aren’t met. If the CPU isn’t installed correctly your computer will emit a particular beep. Check the manufacturer’s website for POST codes to interpret the beeps; they’re helpful for hardware troubleshooting.