To install a CPU, open the motherboard’s socket lever, align the CPU using its notch or golden triangle with the matching mark on the socket, lower it in without pressing down, close the lever, apply a small amount of thermal paste, and fit the cooler. Then connect the cooler’s fan cable to the CPU fan header.
- Align the CPU’s notch or triangle with the socket before lowering it in.
- Never press the CPU down. It should drop into place.
- Apply thermal paste before fitting the cooler, not after.
- Connect the cooler fan to the CPU fan header on the board.
Before You Start
Work on a hard, non-carpeted surface, and discharge static by touching bare metal on the case before handling the CPU. Have your motherboard out of its box and, ideally, out of the case for easier access, especially for a first build.
Step by Step
1. Open the socket
Lift the socket’s retention lever, and on Intel boards also lift the load plate that covers the pins.
2. Align the CPU
Find the small triangle or notch on one corner of the CPU and match it to the corresponding mark on the socket. On AMD AM5 and Intel LGA boards, the CPU only fits one way.
3. Lower the CPU into place
Gently lower it straight down. It should sit flush without any pressure. Never push it down, since the pins are extremely delicate.
4. Close the socket
Close the load plate if there is one, then lower the retention lever and lock it back under its retaining hook. You’ll feel resistance, which is normal.
5. Apply thermal paste
If your cooler doesn’t come with pre-applied paste, add a small pea-sized dot of a paste such as Arctic MX-6 in the center of the CPU. Too much paste can be worse than too little.
6. Install the cooler
Follow your cooler’s specific mounting steps, covered in how to install a CPU cooler, then tighten the mounting screws evenly in a crossing pattern.
7. Connect the fan cable
Plug the cooler’s fan connector into the header labeled CPU_FAN on the motherboard, not a case fan header. ASUS Support and other motherboard makers publish header diagrams for their exact boards if yours is unclear.
Warning: bent pins are the most common CPU installation mistake. Never force the chip into the socket, and always lift it straight up and down rather than at an angle. See bent CPU pins if you suspect damage.
After Installation
Close the case, connect power, and boot. If the PC doesn’t post, power off and recheck the CPU is seated and the cooler is making even contact. Once in Windows, confirm everything is recognized with CPU-Z or what CPU do I have, and check the chipset drivers are current using how to update CPU chipset drivers.
On the RAM side: how to install RAM.
Frequently Asked Questions
Which way does a CPU go into the socket?
Match the notch or golden triangle on the CPU with the corresponding mark on the socket. Modern sockets only allow one correct orientation.
Do I need to apply thermal paste myself?
Only if your cooler doesn’t come with paste pre-applied. Many stock and aftermarket coolers ship ready to install.
What happens if I install a CPU wrong?
Forcing it in the wrong orientation or at an angle can bend the delicate pins on the socket or the CPU, which can prevent the system from booting.
Do I need to press the CPU into the socket?
No. A correctly aligned CPU drops into place under its own weight. Pressing it down risks bending pins.
Frequently Asked Questions
Which way does a CPU go into the socket?
Match the notch or golden triangle on the CPU with the corresponding mark on the socket. Modern sockets only allow one correct orientation.
Do I need to apply thermal paste myself?
Only if your cooler doesn’t come with paste pre-applied. Many stock and aftermarket coolers ship ready to install.
What happens if I install a CPU wrong?
Forcing it in the wrong orientation or at an angle can bend the delicate pins on the socket or the CPU, which can prevent the system from booting.
Do I need to press the CPU into the socket?
No. A correctly aligned CPU drops into place under its own weight. Pressing it down risks bending pins.
