This guide takes into assumption that you have already purchased all the parts for your new system and that all which remains is for the physical assembly and configuration to take place. If you are still unsure about which components will go in your system, you will want to finalize your decision on those first, then approach the idea of constructing the system. AnandTech is not responsible for any damaged caused to your system as a result, either directly or indirectly of the methods described in this guide.
Before proceeding with the building process you want to clear out a small portion of a fairly dust free room, hard wood floors are a plus however a wooden table or a workbench is even better. You want to lay out all of the components you have just received on a table near you, as well as place all appropriate screws, mounting brackets, as well as device driver diskettes by the items they correspond to. You will need a Phillips head screw driver, however a flat headed screw driver, and anti-static wrist strap, additional screws, needle nose pliers, and a computer toolkit are optional.
With all of that taken care of, let's start on that system shall we?
At the heart of every computer is the CPU, which is placed on the motherboard, which parks the peripherals, which drive the storage devices, which are stored in none other than your computer's case. While that mental diagram is remnant of playing a little one on one with your neighborhood point guard it is as simply put as it can be. The case should be the first thing that is opened and inspected before proceeding with any custom built system. Removing the case from its often bulky and large box, you want to make sure that there is no external damage to the case itself. When most vendors ship any order that contains an order for a system case, without the request to pre-install or configure any components in the case, the case itself is often shipped in a separate package so be sure that you do in fact receive two packages from the delivery man. The reason for shipping a case in a separate box is to prevent any sort of physical damage to the other parts shipping with your order. If everything looks ok from the interior, you will want to take a peak at the inside of the case to make sure that you have the proper screws, power cables, standoffs, etc... that are necessary to proceed further.
If your case happens to have a lock on it you will want to check the packaging to find the keys if they weren't attached to the case in any way. In the unfortunate event that the keys didn't ship with the case and the door happens to be locked, most suitcase keys will work fine provided that the key hole isn't spherical, in which case you will want to remove the external housing of the case and unlock the door from the inside by pushing the locking lever out of its resting place. As paranoid as that may seem, it does happen, and sometimes unlocking your case can be a major pain without the proper keys.
Depending on the type of case you purchased, the housing will either come off from the back end of the case or from the front. In the latter situation, the front panel of the case usually pulls off exposing anywhere from 4 - 8 screws which attach the housing to the case's frame. This is how most Enlight cases open. If your housing can be removed by pulling it off of the rear of the case then you want to look at the back of the case and remove the individual screws (once again anywhere from 4 - 8 depending on the type/size of case) therefore freeing up the housing for removal. The most user friendly cases are those which allow you to individually remove portions of the housing, such as the Supermicro design which splits the housing into three sections: a left door, a right door, and a top. Each of those three sections can be removed individually for easy access to any components contained within the case.
Taking a look at the inside of your case, you want to check for a bag of screws/stand-offs, a power cable, keys (if applicable), and any extras such as feet for the case or an alternative ATX backplate if you have an ATX case. If you do happen to have an ATX case, and provided everything looks physically ok on the inside of the case, you will want to examine the 2 - 4 pin power switch wire which will usually be the longest wire in the case running directly from the ATX power switch. Make sure that the cable hasn't been cut and that it is securely attached to the power switch (all of the pins that are taped to the connectors on the switch should be covered up, either by electrical tape or some sort of metal casing). Remove all foreign parts from the interior of the case, unscrew/remove any standoffs that have been pre-installed, and make sure that the motherboard plate is free of all obstructions.
There should be three main types of screws included with your case, the first is your standard chassis screw which is used to attach standard devices and peripherals to the chassis, i.e. video cards, hard drives etc... The second is a screw with a smaller diameter than your standard chassis screw which is mainly used to attach your motherboard to the third type of screw that should've been provided with your motherboard, the stand-offs. Standoffs are screwed onto the motherboard tray of your case and separate the motherboard from the tray by about 1/8". In order to hold the motherboard in place, standoffs contain a threaded opening at the top which will accept the second type of screw discussed above through the holes on your motherboard. Owners of AT cases will find that usually only two or three metal stand-offs are included with their case, while ATX cases ship with close to 10 or 12 metal stand-offs. The reason for this is that AT cases usually rely on the cheaper and more flimsy plastic stand-offs that snap into your motherboard, while this approach is a bit more clumsy than the metal standoff approach it is something you should be prepared for.
Now that the case is clean and ready for installation, set it aside as we prepare the motherboard for installation.