ASSEMBLE YOUR MATERIALS:

• Selecting the processor, motherboard, and memory
• Selecting a case
• Selecting a hard disk
• Extra drives, aka "should I bother with a floppy?"
• Video cards
• Audio cards
• Networking
• Monitors, printers, and all that extra stuff

PUT IT ALL TOGETHER:

• Tools and precautions
• Inspection and preparation
• Pre-assemble the motherboard
• Install the motherboard and expansion cards
• Install the drives and power supply
• The MAGIC SMOKE test...

jump to: Selecting Memory—Selecting a Motherboard

Selecting a Processor

This is about the most important decision you will have to make. There is a reason that PCs are, to some extent, defined by the processors they use. When you describe your rig, the first thing you say about it is "it's a P-4 with..." or "it has an Athlon 2.8 gig processor and..." or something very much like that. Before you decide anything else, you have to decide just how fast you want this rig to be

The key factors to consider are:

• Processor brand and type
• Processor speed (frequency), obviously
• Size of the L2 (level two) Cache
• Front-side bus speed (frequency)
• Socket type

Processor Brand and Type

Functionally there is very little difference between an AMD processor and an Intel. There has been very active debate for several years over which is the "better" processor, but the fact of the matter is that even the hardest- of hard-core gamers would not be able to differentiate between a high-end Intel and a high-end AMD if you sat them down in front of a blank box and asked them to guess. There was a time, as recently as a couple of years ago, when it could be fairly said that AMD processors outperformed Intel at similar processor frequencies (although AMDs did tend to run hotter), but Intel has since bridged the gap and it is now a continuing horse race to see who has the better unit.

Dual Core, Thy Time Has Come

When dual-core processors hit the market, my first recommendation at the time was somewhere between "don't bother" and "wait and see." Just about anything a user could do, even up to hard-core gaming, was served more than adequately by the then-standard technology. Software continues to increase its hardware requirements, however, allowing the dual-core processors to rise to their deserved prominence. Today, prices are more competetive with the previous generation, but that generation is not quite obsolete, so the cumulative effect is the greatest range of processor choices to date.

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Processor Speed (Frequency)

The speed of a processor is measured in hertz, which reflects the number of calculations it can carry out per second. Higher frequency means more calculations per second which translates to faster performance overall—compared to other processors in its category. Intel passed the 1-GHz (one gigahertz, or one billion Hertz) milestone late in the evolution of the Pentium III class of processors, and two to three GHz is now considered standard by most accounts.

Size of the L2 Cache

The L2 Cache is kind of a liaison between the processor and the main memory. Strictly speaking, it actually works between the memory and the L1 Cache, which is kind of the main gathering area for instructions waiting to be processed by the core. These graphics depict the data hierarchy for single- and dual-processor systems, with information moving upward and downward among all levels. In the dual-core hierarchy, information does not move directly between processors, or between L1 Caches; it must move to the L2 Cache and thence over to the other side. Note that in some processors there was a new element, the L3 Cache, which was roughly analogous to the L2. With the advance from 130 nm technology to 90 nm, the L3 Cache largely went away.

Intel Celeron and AMD Sempron processors are more or less equivalent to standard processors, but with reduced (or in the case of some Pentium III Celerons, nonexistent) L2 Caches. This results in reduced multitasking performance, but not much else. Gamers, don't skimp: get the standard-issue processor. Surfers, since you'll mostly be using no more than two or three concurrent applications (web browser, email, and IM client), consider the cost savings; a Sempron or Celeron will likely serve you just fine. Workers, base your decision on the type of work you're doing. If you typically work in one spreadsheet at a time, even if you have your email client open continually, you'll probably be just fine with a Celeron or Sempron. If "work" means lots of virtual meetings, graphic design, and code development, on the other hand, consider yourself just a different flavor of Gamer.

The typical size of the L2 Cache depends on which generation of processor you're considering. A Pentium III processor, as well as some Pentium 4s and Athlon XPs, might have a 256 or 512 KB L2 Cache. A later Athlon XP or Pentium 4 might go up to a full megabyte. The current crop of Core 2 Duo and Athlon 64 dual-core processors have L2 Caches of at least 2 MB as a matter of course. Intel has also introduced the Core 2 Quad processor, but compatible motherboards are few and pricey.

Note that the L2 Cache is distinct from other caches that you might see referenced, such as the "disk cache." The L2 Cache specifically refers to the processing area described above, and is generally included by the "CPU" (Central Processing Unit) along with the L1 Cache and the processor itself. The disk cache, on the other hand, might refer either to a sector of the hard disk reserved for data transfer use; or it might be something application-specific like a software buffer. I shall always refer to the L2 Cache as the L2 Cache for greatest clarity.

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Front-Side Bus Speed

This is one of the most undervalued and under-considered aspects of a processor. The Front-Side Bus or "FSB" is the speed (frequency) at which the processor can communicate with the motherboard and memory; the processor speed applies only to internal data transactions. In the graphics above, communication occurs at full processor speed only among the processor and the Cache areas; once the information leaves the Cache and thereby the CPU, it's moving at FSB speed. A fast processor with a slow FSB may perform no better than a slower processor with a faster FSB.

The key point is not to get a good, fast FSB, but rather to make sure that your processor's FSB is compatible with your motherboard. Mismatching among these components can result in drastically reduced speed, if not outright inoperability. In this regard, selecting these components can become an iterative process: First you pick the processor you want, then you pick a compatible motherboard and memory. You add up the total cost and it's horrendous, so you reduce your requirements somewhat in one or more of the components. Depending on what you change, you then have to check to make sure the others are still compatible. If not, then they get changed, which might result in other changes. It can help to prepare a list of several combinations and then decide based on the overall value.

A good current standard FSB is 800 MHz. A year or two ago this would have been cutting-edge; today it's just a nice middle-of-the-road frequency. On the low end, you could also select a 533 MHz FSB, which will still provide excellent results for Surfers and some Worker types. On the high end, you can go up to 1066 MHz, but be prepared to pay for it.

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Socket Type

The socket refers, literally, to the socket into which the processor will be plugged on the motherboard. No particular socket should be a deal-breaker unless you're looking at the real outer limits of the current technology. This is simply something to remember when you select your motherboard. Unfortunately, sockets have not been cross-compatible between AMD and Intel since the K6-2/Pentium II days, so by selecting a processor brand you have also just narrowed down perhaps the broadest category of available motherboard. Intel currently uses a 423-pin, a 478-pin, and a 775-pin (actually 775-"Land" but the distinction is nil from a practical perspective). AMD has a 754-pin, a 939-pin, and their AM2 which uses 878 pins.

jump to: Selecting a Processor—Selecting a Motherboard

Selecting Memory

The memory selection is typically straightforward, but can have repercussive effects on the selection of the motherboard and processor. This page is laid out in what I feel is the best order to start, so memory should generally be selected immediately after selecting the processor. As depicted above, the memory is the primary communication conduit between the hard disk and the CPU.

The key factors to consider are:

• Clock speed
• Capacity
• ECC error checking
• Brand or manufacturer

Clock Speed

This is similar to the FSB of the processor, and somewhat related although independent. The clock speed refers to the effective data transfer frequency of the memory. Older SDRAM (Synchronous Dynamic Random Access Memory) modules, as used with AMD K6-2, Intel Pentium II, and later processors, is limited to 133 MHz Clock speed. DDR SDRAM (Double Data Rate SDRAM) achieved greatly increased Clock speed by virtue of parallel processing, which not only increased the memory bandwidth but also doubled the effective frequency, so for example DDR memory that operates at 200 MHz has a Bus speed of 400 MHz, and a Clock speed of 3200 MHz by virtue of the increased bandwidth. Operating frequency is rarely reported for DDR modules; instead they will be rated by Bus and Clock speeds. DDR2 is not twice again the frequency, as the name might imply, but rather a second generation capable of performing at even higher Bus speeds. Traditional SDRAM memory tops out at 133 MHz, and that's all you get. DDR memory can reach Clock speeds of up to 3200 MHz (400 MHz Bus speed). DDR2 can currently achieve Clock speeds of 6400 MHz (800 MHz Bus speed).

Note that Bus speed should not be confused with the processor's Front-Side Bus speed; the memory Bus speed refers to the speed at which the memory can communicate with the motherboard, as it does for the processor. For this reason, some purists will say that the memory Bus speed should be an even multiple of the processor FSB, but this has not yet been proven to my satisfaction. As I see it, in order for this to be valid, a 533 MHz FSB processor working with PC2100 memory would have to outperform the same processor working with PC2700 on a compatible motherboard, and it will not. That being said, however, and considering the ubiquity of every possible memory configuration, Gamers at least should probably try to optimize their Bus speeds in order to ensure maximum processing performance, just in case it really does hold true. This means that an 800 MHz processor would be well matched with PC3200 DDR memory (if not PC6400 DDR2).

A good way to conceptualize the internal communications of your PC would be as follows: The motherboard uses four different communication "channels" (this is not the technically correct term, but works fine for visualization's sake): a channel for the processor, which will operate at the frequency of the processor's FSB; a channel for the PCI bridge operating at 133 MHz, or the PCI Express (PCIe) bridge running at a significantly faster rate; the ATA channel for the drives, running at 133MHz on the EIDE channel for PATA hard disk drives and optical drives, and typically 150 MHz or 300 MHz for SATA hard disk drives; and a channel for the memory, which will operate at the memory's frequency. SDRAM will operate at the same frequency as the memory channel, either 100 or 133 MHz. DDR (and DDR2) SDRAM will operate at a Bus speed which is twice the channel frequency, and a Clock speed which is eight times the Bus speed.

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Capacity

In other words, size. More is better, end of story. The only question is how much more do you need? For Gamers, I would say the sky's the limit. Get and use as much as your motherboard will accommodate, and when it won't hold any more, consider upgrading your motherboard. Surfers can realistically do well with 512 MB, or even 256 MB depending on how much full-motion video you watch online. Workers and other users, again, should match their memory needs to the task at hand, and remember that video processing (and intensive audio processing) will be smoother with more memory.

Take note of your motherboard's memory channel configuration when selecting a total memory capacity. If you motherboard supports dual-channel memory (this will typically be advertised prominently), you will actually get significantly better performance out of, for example, 1 GB worth of memory if you use two 512-MB modules of identical manufacture, paired in two memory channels; as opposed to using a single 1-GB module. By splitting channels, you are essentially adding a layer of parallel processing to the already elevated bandwidth of DDR and DDR2 memory (paired memory channels was/is not available for SDRAM).

ECC Error Checking

In my opinion, this is worthless. It essentially takes the 8-bit memory channel and adds a ninth bit as an error check. The overall effect is slower speed and higher cost, for the advantage of very slightly more reliable data transfer. This should only be considered if you work with heavily encrypted files or do a lot of large internet file transfers; otherwise there will be no benefit from the extra money.

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Brand or Manufacturer

This is of much greater importance than many will credit. The unfortunate fact is that memory is not memory is not memory. Some brands are noticeably and significantly more reliable and better performing than others. Please note before reading on that I do not directly advertise any memory manufacturer on this site, so I like to think that my opinions here are, for the most part, unbiased. That being said, I recommend Kingston, PNY, Viking, and Corsair brands above all others. As a second choice I would go with Memorex, Sony, Edge, or SimpleTech, but I will generally not go lower than that. PQI, for example, will not be used in any rig I build for some time yet.

All of that being said, remember that these are my opinions, and if there is a particular brand to which you are loyal and from which you have got reliable performance, then by all means continue to use it. My experience is in no wise so broad-reaching as to be able to consider myself an ultimate authority on memory brands.

jump to: Selecting a Processor—Selecting Memory

Selecting a Motherboard

Having selected a processor, the next step is to select a compatible motherboard. The motherboard will be the communication nexus among the processor, memory, hard disk, optical drives, floppy drive (if present), expansion cards, and anything else you've crammed into the case. Selection criteria are different, but at least equally important.

The key factors to consider are:

• Bus speed (frequency)
• Bridge type; PCI/PCI-X/AGP vs PCIe (
• Number and type of expansion slots
• Number and type of drive interfaces
• Headers for front ports (USB, audio)
• Number and type of memory slots
• On-board peripherals (and back ports)
• Form factor
• Additional toys

Bus Speed

If you've already selected your processor then you know what Bus Speed (as FSB) you need. This is the speed at which the motherboard communicates with the processor, so it must be compatible. Communication with the expansion cards (PCI/PCI-X or PCIe bridge) will be somewhat slower, but will be based in part on the FSB. Communication with the drives will be at an even slower fixed speed.

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Bridge Type: PCI/PCI-X/AGP vs PCIe

Prior to the Pentium 4/Athlon XP generation of processors, PCI ("Peripheral Component Interconnect") was the standard interface "bridge" (communication channel, basically) for expansion cards, and many modern boards still include PCI (or PCI-X) slots. The original standard for the PCI bridge specified an operating frequency of 33 MHz and a bandwidth of 32 bits per cycle (a Hertz is a cycle per second), for a total theoretical data transfer rate of 133 megabytes per second, or MB/s. This was later increased to 266 MB/s by doubling the bandwidth to 64-bit, and then to 533 MB/s by doubling the frequency to 66 MHz.

PCI was later extended to PCI-X (PCI "eXtended," predictably enough) which initially operated at 133 MHz, effectively doubling the theoretical maximum data transfer rate. This was later increased to 266 MHz and then to 533 MHz, making the effective data transfer rate 4.3 gigabytes per second (GB/s) for a 64-bit channel, or 2.1 GB/s on a 32-bit channel. As for the actual cards, there was (is) a difference in operating voltage, so while a PCI-X slot might be able to run a PCI card, a PCI slot would probably not run a PCI-X card. PCI slots are rare, however, and most expansion slots that are listed at PCI are actually PCI-X.

AGP ("Accelerated Graphics Port") is a further development of PCI, specifically intended to accommodate advances in video card technology. The different generations of AGP use increasing clock multipliers—a method of increasing communication rate by sending multiple 32-bit "bursts" per hertz—to provide faster graphics data transfer. AGP also allows the video card to communicate directly with system memory (as opposed to PCI/PCI-X which communicated only via the PCI bridge) to provide much faster video rendering.

The newest player is PCIe ("PCI Express"). PCIe uses one or more 2.5 GHz "lanes" communicating at one byte per 10 hertz for a data transfer rate of 250 MB/s per lane. The number of lanes used by a PCIe card will be specified as a multiplier rating, e.g. ×1, ×8, ×16. The maximum data transfer rate achievable by current PCIe cards is therefore 250×16=4.0 GB/s, much much faster than PCI, PCI-X, or AGP. PCIe is expected to entirely supplant all previous standards. In addition, the newest PCIe standard specifies a per-lane data transfer rate of 500 MB/s, although support for the PCIe 2.0 standard is still spotty.

There is another specialized interface type, SLI ("Scalable Link Interface") by nVidia or CrossFire by ATI, which were developed for next-generation video cards. SLI and CrossFire use two adjacent PCIe channels to provide perhaps the most powerful video processing available. Support for SLI and CrossFire is increasing, but a very high-powered system is needed to handle the data load.

Note that some PCIe-compatible motherboards also have an AGR ("Advanced Graphics Riser") slot, which allows backward compatibility with AGP video cards.

Note also that PCIe is full-duplex, meaning that data can move in both directions simultaneously, as opposed to PCI/PCI-X/AGP, which are half-duplex. This means that although PCIe ×4 has the same data transfer rate as PCI-X, performance will be better with a PCIe card because the total amount of transferred data can be twice that of PCI-X.

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Number and Type of Expansion Slots

This is relatively simple, but absolutely must not be overlooked. There are motherboards on the market right now with integrated audio, video, and broadband and dial-up networking, and no expansion slots. It would truly be a shame to go to all the trouble of matching specs and ratings on all of this stuff, only to have it arrive without any way to actually connect your new video card to your board. This should also be considered in conjuction with the bridge type to make sure everything remains compatible when it comes time to select the expansion cards.

Number and Type of Drive Interfaces

Optical disk drives will either be PATA (ATAPI) or USB. Floppy disk drives may also be USB, but more frequently use a standard floppy drive interface. A hard disk drive can be PATA (IDE), SATA, or occasionally USB (not as common).

PATA ("Parallel Advanced Technology Attachment") is the term which has now superseded IDE ("Integrated Drive Electronics"), EIDE ("Enhanced IDE"), and ATAPI ("Advanced Technology Attachment Packet Interface"). It refers to the interface used by optical drives (CD, DVD, HD-DVD, or Blu-Ray™) and hard disk drives. Transfer rate is a maximum of 133 MHz, although older interfaces operated at only 100 or even 66 MHz.

SATA ("Serial ATA"), is the new emerging standard for hard disk drives. There are currently two primary speeds supported, 150 MHz and 300 MHz, and these can be multiplied by the use of certain RAID ("Redundant Array of Independent Drives") configurations—something that was not possible for PATA drives without specialized hardware or software. For example, if you have two 300-MHz SATA drives set up as a RAID-0 ("Striped") array, you can write to each drive simultaneously, making your effective data rate 600 MHz. Plus, if each drive is 200 GB, the total size of your striped drive will be 400 GB (for different sized drives, twice the size of the smaller drive). SATA drives are much faster and a great deal more versatile, but they do not share a common interface with the still-common (and still-standard) PATA drives. If you know you'll be using SATA hard drives, make sure to select a motherboard with at least as many SATA interfaces as you have drives. Even if you pick a motherboard without SATA interfaces, you can still use SATA drives along with an appropriate expansion card.

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Headers for Front Ports

This is primarily a practical decision and, like the socket type of a processor, should not be a deal-breaker. If you expect to buy a case with front-panel USB ports (or FireWire, or headphone jacks), you will probably want a motherboard with appropriate connectors built-on. If your board doesn't have them (and there are precious few left that don't anymore), you can still buy an expansion card that has them. For audio in particular, if you intend to buy a separate audio card instead of settling for mediocre on-board audio, you can always get one with some kind of external audio header.

The USB (or other) headers can also be used for other front-side gear, such as memory-card readers. Make sure to keep this in mind as you make your selections.

Number and Type of Memory Slots

The number of USB headers may or may not contribute to your final decision. The number and type of memory slots, on the other hand, may well be a deal-breaker. Since you must choose all three of these components together, you must choose a motherboard with the correct type of memory slots. Memory slots will be SDRAM, DDR, or DDR2. Memory choice will be largely determined by what the motherboard supports. Your intended use will drive the number of slots, but below about 1 GB of memory you should be able to get what you need with even one slot if that's all the motherboard has.

On-Board Peripherals (and Back Ports)

On-board peripherals are sometimes referred to as on-chip devices. This is a general term for any peripheral function (video, audio, networking) that is built in to the motherboard, either with appropriate back ports or with available headers for front port connections. There are several typical on-board peripherals:

• Audio: Gamers, don't bother. You'll want your own sound card. For other users, on-board audio should sound just fine unless you plan to do extensive audio mixing and editing.
• Video: Same as audio. If you plan to do extensive gaming or video mixing and editing, don't bother, get a video card instead.
• Networking (NIC): This one should be okay for all users. An ethernet card offers almost no advantage currently over an on-board networking chip. If you will be using broadband, look for on-board networking.
• Parallel ports: If you have an older printer (by "older" I mean three years old or more) that does not have a USB connection, a parallel port will come in handy. Otherwise, only consider this if you know you'll specifically need it for some other device (non-USB scanner, for example).
• Serial ports: No one uses serial ports anymore. For anything. Actually that's not strictly true, but the typical user is highly unlikely to actually need one. Like the parallel port, only consider this if you specifically have a device that requires it.
• USB: Definitely get on-board USB. Good luck finding a board without it, in fact, but you should verify that your board has headers for front ports if you think you'll need them.
• Modem: Same as Networking but for dial-up service. There is no advantage to an expansion card over an on-board jack, but make sure it's at least V.92 if you want to make sure you're current.

Other options may vary among boards, but these will be by far the most common. Don't let any of these be a deal-breaker, though; if you find an absolutely awesome motherboard that happens not to have on-board [insert peripheral name here] then just make sure you remember to buy an appropriate card. Keep that in mind as you decide on your minimum number and type of expansion slots, though; any on-board peripheral can be replaced by an expansion card, but you will have a very difficult time getting more expansion cards than your board came with.

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Form Factor

This should be noted, but again, is not a deal-breaker. The only time you need to consider this is if you pick a board with an unusual form factor like Nano-ITX, because you may have a more difficult time finding a case to accommodate it.

Additional Toys

There are any number of other options that a motherboard might have built in: multicolor LED headers, on-board FireWire, extra fan headers (or on-board ACPI fan controllers), removable EEPROM BIOS, back side heat spreader, etc. etc. etc. If there is any particular gizmo that you absolutely had your heart set on then now is the time to figure it in to your decision. Otherwise, just take what you get as a bonus.

There are also a number of additional on-chip devices that will not be treated in extensive detail here. If you're comparing north bridges and south bridges or such like, then you're either being far too anal-retentive, or you are truly a dedicated technophile, and likely a Gamer far surpassing my meager provender. You will have to find detailed information elsewhere, and I will humbly suggest the manufacturer's website. I shall offer no further advice except to say good luck and godspeed.

Types of Computer Users

There are three broad classifications of computer users: Gamers, Surfers, and Workers. Some will argue that there should be a fourth classification, "n00bs" (yes, that's spelled correctly, you n00b), but they won't generally go in for rigbuilding so they will not be considered here.

When I talk about Gamers, I'm not talking about people who while away a lazy Sunday afternoon playing Minesweeper. Neither am I talking about those who spend most of their time on Shockwave.com or MSN Games. Gamers play World of Warcraft, Everquest, Shadowrun, Halo 2, and other high-action graphics-intensive games. A Gamer will need a fast processor with a big L2 cache and a fast front-side bus.

Surfers, on the other hand, are the Great Communicators. They spend most of their time surfing the web, emailing, Instant-Messaging, updating their blogs, or posting video to YouTube. For the most part, Surfers don't need speed, they need reliability; sticking with market standards and keeping a little ways back from the cutting edge will serve them well. A good-sized hard disk will certainly come in handy, too.

Workers are the in-between class. This refers to anyone who uses their PC not because they want to, but because they have to (or because they feel they have to). This moniker would aptly describe just about any office employee, but also anyone who mostly uses their home PC for maintaining bank records, tracking vehicle maintenance; in short, anyone to whom a PC is less a toy than a tool. In the table below, Workers would fall anywhere between the extreme represented ends of the spectrum; it depends entirely on the nature of the work done. Simple financial work and word processing can be handled by the "reliability" end. Video or audio editing or programming will likely move more toward the "performance" side.

Next Step: Selecting a Case