Step 2: Memory and Processor

The innards of computers are designed to optimize space and airflow, not to insure all components are accessible at all times. Because of this, it?s important to follow a certain order in installing components to make life easier (and prevent having to pull out stuff you’ve already added). The first component that we will add is the memory. All modern memory comes in the general form of a DIMM module. Modules are keyed so that they only fit in the slot one way, and will only fit in compatible slots. You want to fill slots starting with the largest module in the lowest numbered slot (there should be some indication on the motherboard or in the documentation as to which slot is slot 0). To insert a module, first press down the white tabs on the end of the slot, then press the module firmly and evenly into place. Some of the key patterns are nearly symmetrical, so if the module doesn’t seem to go in at first, try flipping it around. As the module goes in, the tabs should swing up to clip it into place.

The next component to install is the processor. Because of their expense and fragility, modern CPUs are connected to the system through a ZIF, or Zero Insertion Force, socket. One corner of the CPU should be chamfered, or be indicated with a dot. This will match with a corresponding chamfer on the socket. Once you’ve found the appropriate orientation, you need to open the socket by pulled the locking lever out and up. The ‘out’ motion is really just a slight bend to unlatch the lever. The lever should lift to be perpendicular to the motherboard. Now that the socket is open, carefully set the processor on the socket. It should slide into the socket under its own weight. When it is properly seated, push the locking lever back into the locked position.

The heatsink is a critical component to keeping your PC running. The interface between the processor and the CPU is important. Some heatsinks, including most of the stock ones provided with boxed CPUs, come with thermal tape on the bottom. If your heatsink did not come with thermal tape, I would recommend applying a thermal compound to make a good thermal interface. Instructions for applying the compound should come with it, otherwise you can read below to special circumstances. The heatsink can attach to the computer in one of two ways. The first and more common method is by clipping to the processor socket. For some large, heavy heatsinks, you need to bolt them directly to mount points inside the case. Since mounting systems differ, and require that the motherboard be configured and drilled to accommodate them, I will leave installation of these to the instructions included with the part.

Before installing the heatsink, you may need to attach the fan if it is not already mounted. This is usually accomplished by screws on the corners of the fan or by wire clips along two edges. The best airflow direction for the heatsink fan is blowing down into the heatsink. Fan direction should be indicated by arrows on one side on the housing.

A heatsink clip is typically a bent metal strip that passes through the middle of the heatsink. The ends of this strip have holes to latch onto protrusions from the processor socket. The idea is to place the heatsink centered over the processor, and maneuver one end of the mounting bar to one of the protrusions. The best way to get the other end on is to pull out and down, pressing towards the protrusion on the other side of the socket. Typically, the mount points on one or both sides have a taper; it?s a good idea to make the second side one with a taper so that it?s easier to clip into place. Note that it takes a good deal of force to get the bracket to clip into place. You want to be careful to apply even pressure and to not shift the heatsink a lot while clipping the bracket into place.

Once the heatsink is in place, you want to connect the fan to power. The three typical ways this is accomplished is through a motherboard header (a thin 2 or 3 pin connector), a 3-pin bus connector, or a 4-pin drive power connector. Motherboard headers will be indicated on the motherboard. 3-pin connectors use either an adapter to connect to a drive power connector, or connect to a fanbus. 4-pin “molex” drive connectors can connect directly to a hard drive power connector. Since the last two connection options involve stringing a cable across the case, it may be easier to leave connecting it to later.

Step 3: Cables

The main cables that you want to get connected before adding expansion cards are the drive data cables and the motherboard power connector(s). The three drive cables that you may need to connect are the floppy cable, IDE cables, and SATA cables, depending on your drive configuration. The floppy cable is the narrower of the two ribbon cables that should have shipped with your motherboard, and has a twist in some leads before the last set of connectors. The floppy connector is usually labeled on the motherboard as such. You only need to have this cable in place if you’re using a floppy drive (I recommend having one, as they’re sometimes helpful, and cheap).

Most motherboards have two IDE channels, which support two devices each. Deciding on the layout of devices on these channels I will discuss later, for now you can assume that they will both be needed. Both the IDE and floppy ribbon cables are keyed to only connect one way; if the keying is not present, put the colored edge of the cable towards the pin indicated as pin 1 on the motherboard header. For SATA drives, you want one cable per drive connected to the motherboard SATA controller. If you’re using a PCI card as an IDE or SATA controller, you don’t need to connect those cables at this point.

Motherboard power is supplied through a large rectangular connector. It is keyed to connect to the motherboard only one way, and clips into place. On some Pentium 4 motherboards, an addition Pentium 4 power connector is required. This is a square 2×2 connector that connects to a corresponding, keyed, connector on the motherboard. If your motherboard requires this connector but your power supply does not provide it, there are adapters available to convert a hard drive power lead for this purpose.

Front panel connectors are what make your power and reset buttons work and the power and hdd lights glow. There should be a block of headers on the motherboard where all of these connect. This is usually one of the more poorly documented parts of the motherboard layout; usually you can find an indication of where in the header block the connectors go, though the direction is sometimes ambiguous. Since power and reset are momentary switches, polarity isn’t tremendously important, but the power and hdd LEDs need to be connected the right way. Often, the only way to check is to move things around every time the computer is off until its right.

Step 4: Drives

Drive mounting patterns vary by personal preference, but I like to space out my optical drives if possible starting from the top of the case down, and do the same with hard drives starting at the bottom of the internal bays. Drives mount to the cages either by screws or by mounting rails. Rails are easiest; you attack the rails to the drive outside the case and just push it into position from the front (for hard drives, this may require removing the faceplate of the case). If the drives need to screw in, you slide the drive in from the most convenient direction, lining it up as well as possible. You then insert 4 screws loosely (less screws are possible, but 4 is more secure. Especially difficult are screws on the back side of the case, which often require guiding through small access holes. After you’ve got all four screws in place, align the drive just right (especially important for the appearance of optical and floppy drives) and hand tighten.

One special case that can occur with hard drives is a lack of the 3.5″ bays that they use. For this purpose, most drive manufacturers provide adapter rails to mount the drives in 5.25″ bays (near the optical drives). I’d recommend doing this only if you need to, for reasons of wasted external bays, thermal problems, and cable run issues. You attach the adapters to the drives before inserting them into the case. Note that drive rails also work in this situation.

Now is when I will talk about the art of assigning drives to IDE channels. With the advent of SATA, this is becoming less of an issue, but most system builders will still benefit. Transfers between drives on the same IDE channel are slower than transfers between drives on separate channels. For this reason, optical drives should be split up to speed CD copying, and hard drives should be split up to speed things like video editing, which work better reading from one drive and writing to another. For this reason, I recommend the following layout:

Primary Channel:
-Master: Primary Hard Drive (OS, apps)
-Slave: Primary CD (fastest burner)
Secondary Channel:
-Master: Secondary Hard Drive (Data)
-Secondary CD (DVD, etc)

IDE connectors should be keyed to connect to the drive only one way; if not, the colored edge goes towards the power connector on the drive. The master connector on the IDE cable is the one at the end, the slave is the one in the middle. Drive power is supplied through 4-pin molex connectors (on IDE drives) or SATA power connectors (on SATA drives). Some SATA drives accept 4-pin molex connectors, though this disallows some of the power features of SATA, such as hot swapping. If your power supply doesn’t have SATA connectors and your drive requires them, there are adaptors available (note that these also disallow special SATA power features). The floppy power connector is a smaller 4-pin connector, the widest edge of this faces down.

Now that your home server is built hook it up to a monitor, keyboard and mouse and plug it in. If everything went correctly you can set the date, time and other options in the bios. If you have any problems then retrace the steps. If you still have problems then stop by Extreme Tech Support forums so we can help troubleshoot the problem.