Populating the motherboard
With the case prepared, the next step is to populate the motherboard by installing the processor and memory. It's much easier to do this before the motherboard is installed in the case. You're also less likely to damage the processor, the memory modules, or the motherboard itself if you keep the motherboard on a firm, flat surface while installing the processor and memory.
To begin, locate the processor socket and raise the ZIF (zero insertion force) lever to vertical, as shown in Figure 5. Make sure the lever comes to full vertical, or even a bit beyond.
Figure 5. Opening the ZIF lever on the processor socket
With the ZIF lever vertical, drop the Sempron processor into the socket. Make sure that the gold triangle on one corner of the processor is aligned with the corner of the socket where the ZIF lever attaches, as shown in Figure 6. The processor should just drop into place, without any pressure being applied. If it doesn't, move it around slightly to make sure the processor pins are aligned with the socket holes. If necessary, apply very slight pressure to make sure the processor seats fully.
Figure 6. Installing the processor
When you are sure the processor is fully seated in the socket, press the ZIF lever down until it locks into place, as shown in Figure 7. This locks the processor into the socket and makes electrical contact between the processor pins and the socket.
Figure 7. Locking the processor into the socket
We actually used an OEM Sempron processor that we happened to have on hand, rather than the retail-boxed Sempron we listed in Part 1 of this article. That meant we needed a CPU cooler. We found a Dynatron DC1206BM-L/610-P-Cu in the workroom that had been on the shelf for a while.
The fastest CPU listed on the box was the Athlon XP 2600+, so it seemed likely this cooler would be good enough for a Sempron 2400+. To verify that, we checked the AMD Sempron Thermal Solutions page and found that the DC1206BM-L/610-P-Cu is now rated for processors as fast as the Athlon XP 3200+ and Sempron 3000+, so it's easily good enough for a Sempron 2400+ (or for the Sempron 2800+ we actually used). The DC1206BM-L/610-P-Cu is an inexpensive cooler--$7.50 at NewEgg--but it's still more efficient and quieter than the stock cooler, so perhaps it's just as well we used it instead of the stock cooler.
The Dynatron cooler is physically similar to the stock CPU cooler supplied with retail-boxed Sempron processors, so you can use the same procedure we describe if you use the stock AMD cooler. To begin installing the CPU cooler, peel off the protective cover to expose the phase-change thermal pad, shown in Figure 8.
Figure 8. Exposing the phase-change thermal pad before installing the CPU cooler
AMD is very specific about which thermal compounds should be used with its processors (PDF file). For what AMD calls lidless processors--those in which the processor die is exposed--it recommends using a phase-change thermal pad rather than thermal grease. AMD also recommends against using silver-based thermal compounds, concerned that they may cause electrical shorts and damage to the processor and motherboard. Despite this advice, we would ordinarily have used silver-based thermal compound with our lidless Sempron, because we dislike phase-change pads. We decided to use the phase-change thermal pad because we were building this system for this article, but we'll probably replace the thermal pad with silver-based compound the next time we tear this system down.
Although we cannot contradict AMD recommendations, we will say that we've been using Antec Silver Thermal Compound for years on all types of processors without any problems. If you follow directions, the risk of damaging anything is vanishingly small. Silver-based compounds transfer heat more efficiently than do silicone-ceramic thermal compounds, which allow slower fan speeds and accordingly lower noise levels. Still, if you follow our advice and your processor burns down, don't blame us. If you want to play by the rules, use the thermal pad supplied with the retail-boxed Sempron.
A CPU cooler installs in only one orientation. Note the "step" on the left side of the CPU cooler base in Figure 8. That step fits a matching raised area on the socket itself. To install the CPU cooler, align it so that the step on the heat sink matches the corresponding raised area on the socket, and place the cooler into position. The CPU cooler is secured by a spring steel bracket with notches on each end that snap over corresponding tabs on the socket base.
Seating the first end of the bracket is easy, because there's no pressure on the bracket at that point. Seating the second end of the bracket requires significant pressure against the springiness of the bracket. Use a small flat-blade screwdriver, as shown in Figure 9, to snap the second end of the bracket into place.
Figure 9. Securing the CPU cooler
With the CPU secured, the next step is to connect the CPU cooler fan to the CPU fan power header, which is located near the processor socket corner where the ZIF lever connects. This cable uses a keyed three-pin connector. Align the connector with the key on connector body matching the key on the motherboard header and press the connector into place, as shown in Figure 10.
Figure 10. Connecting the CPU cooler fan to the motherboard power header
The final step in populating the motherboard is to install the memory modules. (Although we originally configured this system with one 256MB memory module, we intend to use this system for multimedia encoding, so we decided to install a second 256MB DIMM.) If you are installing only one memory module, insert it into the slot labeled DIMM 1.
To install the module, pivot the white plastic retainers at each end of the slot outward, orient the module with the keying notch aligned with the keying tab in the slot, and press the module firmly into place, as shown in Figure 11. As the module seats, the white plastic retaining tabs should pivot back up to vertical, locking the module into place. If not, pivot them into position manually.
Figure 11. Seating a memory module