Components of a server computer

The hardware components that comprise a typical server computer are similar to the components used in less expensive client computers. However, server computers are usually built from higher grade components than client computers for the reasons given in the preceding section. The following paragraphs describe the typical components of a server computer:

• Motherboard: The motherboard is the computer's main electronic circuit board to which all the other components of your computer are connected. More than any other component, the motherboard is the computer. All other components attach to the motherboard.
  The major components on the motherboard include the processor (or CPU), supporting circuitry called the chipset, memory, expansion slots, a standard IDE hard drive controller, and I/O ports for devices such as keyboards, mice, and printers. Some motherboards also include additional built-in features such as a graphic adapter, SCSI disk controller, or a network interface.
• Processor: The processor, or CPU, is the brain of the computer. Although the processor isn't the only component that affects overall system performance, it is the one that most people think of first when deciding what type of server to purchase. At the time of this writing, Intel had four processor models, summarized in Table 3-1. Two of them - the Pentium 4 and Celeron - should be used only for desktop or notebook computers. Server computers should have an Itanium 2 or a Xeon processor, or a comparable processor from one of Intel's competitors, such as AMD.
  Each motherboard is designed to support a particular type of processor. CPUs come in two basic mounting styles: slot or socket. However, you can choose from several types of slots and sockets, so you have to make sure that the motherboard supports the specific slot or socket style used by the CPU. Some server motherboards have two or more slots or sockets to hold two or more CPUs.
  The term clock speed refers to how fast the basic clock that drives the processor's operation ticks. In theory, the faster the clock speed, the faster the processor. However, clock speed alone is reliable only for comparing processors within the same family. In fact, the Xeon is significantly faster than the Pentium 4 running at the same clock speed. That's because the Xeon contains more advanced circuitry than the Pentium 4, so it's able to accomplish more work than the Pentium 4 with each tick of the clock.
  
  Intel Processors

  Processors	Clock Speed	Intended Usage
  Itanium 2	1.30-1.60GHz	Servers
  Xeon	1.4-3.6GHz	Servers
  Itanium 4	3.2-3.73 Hz	Desktops
  Celeron	950MHz-3.06GHz	Low-end desktop

• Memory: Don't scrimp on memory. People rarely complain about servers having too much memory. Many different types of memory are available, so you have to pick the right type of memory to match the memory supported by your motherboard. The total memory capacity of the server depends on the motherboard. Most new servers can support at least 12GB of memory, and some can handle up to 32GB.
• Hard drives: Most desktop computers use inexpensive hard drives called IDE drives (sometimes also called ATA). These drives are adequate for individual users, but because performance is more important for servers, another type of drive known as SCSI is usually used instead. For the best performance, use the SCSI drives along with a highperformance SCSI controller card.
• Network connection: The network connection is one of the most important parts of any server. Many servers have network adapters built into the motherboard. If your server isn't equipped as such, you'll need to add a separate network adapter card. See the section, "Network Interface Cards," later in this tutorial, for more information.
• Video: Fancy graphics aren't that important for a server computer. You can equip your servers with inexpensive generic video cards and monitors without affecting network performance. (This is one of the few areas where it's acceptable to cut costs on a server.)
• Power supply: Because a server usually has more devices than a typical desktop computer, it requires a larger power supply (300 watts is typical). If the server houses a large number of hard drives, it may require an even larger power supply.