mechBgon's guide to building your first PC from parts   : )
  1. Start

  2. Case prep 1

  3. Case prep 2

  4. Data and power cables

  5. Serial ATA stuff

  6. General motherboard/CPU info

  7. Testing & installing the motherboard assembly

  8. Installing the hard drive

  9. Final connections

  10. Security during Windows Setup

  11. Best practices for ongoing security

  12. Resources (drivers, diagnostics, links, online antivirus scans, antispyware resources)

  13. A brief visual glossary

Back to the general motherboard/CPU info page

Next: Installing the hard drive

~ Caution ~ Remember that all the parts shown here are easily damaged by static shocks. Frequently touch a grounded object such as the plugged-in computer case before and during the handling of these items.

Your best option is to install the CPU and heatsink while the motherboard is outside the case. Lay it on cardboard.

Below: the heatsink/fan unit that came with this retail-boxed AthlonXP.

click to enlarge

What you should know about SocketA processors

  • The processor core is the small purple rectangle in the center of the green square. The core has very little mass and it begins generating about 50 watts of heat the moment the computer powers up, so it will overheat practically instantly if there's nowhere for the heat to go. The heatsink/fan assembly needs to be fully installed and clipped down before the processor powers up.

  • The heatsink for an AMD AthlonXP or Duron processor is directional. Look at the underside in the photo below, and notice how one end has a step cut into it.

  • In the photo above, see the square patch of phase-change thermal compound? If it's covered with a plastic protective slip instead of this big plastic tray like on mine, peel the plastic off. The compound itself has a gummy feel. It "melts to fit" the microgap between the surface of the CPU core and the surface of the heatsink. It's extremely important for that microgap to have some type of thermal-transfer material to bridge it, and the phase-change type is also intended for exactly one usage, so try to do this stuff right the first time.

  • If you goof up and waste your phase-change thermal patch, don't despair. Get some Coolermaster/Shin-Etsu or Arctic Silver/Arctic Alumina thermal grease, scrape off all of the melted phase-change patch, and apply a paper-thin coating of thermal grease to the processor core. Also rub some into the base of the heatsink where it'll contact the processor core. Covering your finger with a plastic baggie is a good way to apply the thermal grease without contaminating it with skin oils.

Here's the unstepped end of the AthlonXP's heatsink, and notice that the chromed clip has no screwdriver receptacle on this end.

Here's the stepped end of the AthlonXP's heatsink. This end of the clip DOES have a receptacle for a screwdriver tip.

Raise the lever on the side of the CPU socket:

Look at the CPU. Oh hey, it has a gold triangle on one corner.

For a Socket A processor (Athlon and Duron families and SocketA Semprons), the gold triangle needs to go in the position shown below (pointing at the lever), because the CPU has an asymmetrical arrangement of pins and it only fits into the socket this way. This applies to Intel Pentium4's and Celerons too, but NOT to Athlon64.

If your CPU doesn't drop effortlessly into the socket, inspect its pins very closely from all directions... some of them might be slightly bent. Straighten them carefully, or return the CPU if necessary.

Hold the CPU down and lower the lever to secure it into the socket.

The critical moment As you can see, the raised, solid-plastic end of the CPU socket is towards the camera, and so is the stepped end of the heatsink base and the screwdriver-friendly end of the chromed steel heatsink clip. This is the correct orientation. The step in the heatsink's base provides the needed clearance over the raised, solid-plastic end of the CPU socket.

click to enlarge

Clipping down a SocketA heatsink takes a fair amount of force, so don't be shy.  : ) For the record, I can engage these wide three-lug clips with my bare hands, so if you're strong, you might try that first.

  • Find a flat-tipped screwdriver that fits the heatsink's clip snugly, bigger is better (I chose poorly for the photo; the small screwdriver shown is all I had handy).
  • Lay a credit card below the clip to intercept the screwdriver if it slips.
  • Put the screwdriver into the receptacle, and begin pushing down on the clip using the screwdriver.
  • You can also use the screwdriver to lever the clip outwards, so it clears the protrusions on the socket cleanly.

Another option: don't use a screwdriver in the first place. : ) Use a socket-driver, or a screwdriver that's got a hollow shaft to accept interchangeable tips. The hollow end of the driver can go right over the tang that's sticking out of the heatsink's clip, as shown below.

Plug the heatsink's fan into the fan header on the motherboard. I put a loop in the fan's power cable, partly to take out the slack and partly because it may help reduce EMI. Notice that the plug goes onto the header only one way by design, as depicted below.

You can locate the correct fan header by reading the motherboard owners' manual.  : )

Back to the general motherboard/CPU info page

Next: Installing the hard drive