Homebuilt PC Buying Guide

Welcome to my guide! I have included explanations of how to choose parts, my list of recommended parts, and links to other helpful sites. My goal in making this guide is to provide an informative resource that can be used to choose the right parts for any price point and for any use. I am not posting any complete builds because I feel there are too many variables, but if anyone has any questions about how to match up the different parts, see the links below and feel free to ask in the Homebuilt Forum where you'll certainly receive help. I am not posting all parts that I recommend because I'm trying to avoid repetition, so there may be similar alternatives available. Nevertheless, my list will generally contain the best, least expensive products available at the time. Certainly, if you have any suggestions or contributions, please let me know!

Last Updated 11/21/09

Section 1: Identifying a Good Part

When picking any part it is important to reference benchmarks in order to see, regardless of specifications, how the part performs relative to others. Also, read reviews from trusted sources (newegg doesn’t count) in order to determine the quality of the component you are selecting (especially PSUs). Finally, always keep your budget in mind. Throughout this guide I have included links to sites that should help with this.

CPU/Processor
It is best to only compare processor specifications to other processors by the same manufacturer, as comparing the specs of an AMD processor to an Intel one can be misleading. That said, there are a number of specifications you should consider when selecting a processor including:
1. Socket – No affect on performance, but determines compatibility, make sure that your CPU is compatible with your motherboard.
2. Cores – Twice as many does not equal twice the performance; quad cores processors are not twice as fast as dual core ones. Nevertheless, I would recommend quad cores in most cases, especially if you are going to be multitasking or doing highly threaded tasks such as rendering, encoding, animation or Photoshop. If you will be using the computer solely for games that are not threaded to take advantage of four cores, and not multitasking, or just using it for word processing and the internet, then a dual core will be fine. Also, keep in mind that games, operating systems, and other programs are moving towards more cores, and that you can always overclock the quad.
More Info
3. Clock Rate (GHz) – Higher is better, but remember not to compare apples to oranges (3.4GHz Phenom II 965 versus 2.8GHz Core i7 860). If you are forced to choose between a faster dual core and a slower quad core I would generally recommend the quad (see #2 for more info). More Info
4. FSB Frequency (MHz) – Higher front side bus speeds are better. The front side bus is the pathway that connects the northbridge (a part of the motherboard’s chipset) and the CPU. Moving data along the pathway faster and moving more data per clock cycle improves system performance. Look for 1066MHz or higher. One note, this frequency operates independent of RAM frequency; you don’t have to match the RAM’s frequency to this number.
5. Cache (MB) – More is better, cache acts as a buffer in order to prevent the CPU from being forced to access the far slower RAM, and thereby speeds things up and decreases traffic. As seen in the Athlon II series(which lacks L3 cache), processors sometimes operate surprisingly well without any L3 cache (they still have closer, smaller, faster L1 and L2 cache levels). The Core 2 series processors from Intel lack L3 cache as well, but they have large L2 caches instead. More Info
6. Manufacturing Tech (nm) – Smaller is better in terms of heat production, power consumption, and overclocking capability.
7. TDP (W) – Lower thermal design power is better; it’s easier on your power bill, produces less heat, and requires less cooling.
8. HT – Hyperthreading is a technology found in Intel Core i7 processors (and some others). A processor with HT enabled is recognized by the OS as having twice as many virtual cores as it actually has (physical cores). Physical cores are still better than virtual ones though. HT is more beneficial in highly threaded applications. More Info
9. Turbo boost – Feature found in Core i5 and Core i7 processors (and some others) that automatically increases the clock rate of active cores when some cores are inactive. For example, if a quad core processor has a TDP of 100W to be shared by all four cores, but only two cores are active, the processor will automatically increase the clock rate of the active cores until the full TDP is reached. This effectively eliminates any advantage a faster clocked dual core processor might have. More Info
10. BE – Black Edition processors have their multipliers unlocked which can simplify overclocking.

MOBO/Motherboard
Although there are more factors to consider about motherboards then those that I will explain below, I will limit my discussion to the specifications that are applicable to the motherboards I have listed in the next post as many of the other specs are universal to most modern motherboards.
1. Quality – Typically, Asus and Gigabyte make the best boards, while MSI and ASRock can be used on a budget. Less expensive motherboards typically have less overclocking potential than their more expensive counterparts.
2. Chipset – The chipset is essentially the spinal cord of the computer; it determines many things about the motherboard including how many PCI-E x16 slots it has, what RAM it supports, and whether or not it is equipped with onboard graphics.
3. Socket – Your CPU and motherboard must have the same socket, with one exception: AM3 CPUs work with both AM2/AM2+ motherboards and AM3 ones. AM2+ CPUs however, only fit in AM2/AM2+ boards.
4. FSB Frequency (MHz) – Make sure that your motherboard supports frequencies that are at least as high as that of your CPU otherwise you will not be utilizing your CPU to its full potential. Look for 1600MHz (you won’t need that high of a frequency, but it’s a good sign). Again, remember that you don’t have to match the RAM’s frequency to this number.
5. RAM support – Check and see which generation of RAM is supported (DDR2, DDR3) and whether the board supports dual (AM2/3, 775, LGA 1156) or triple channel (LGA 1366) configurations. Look for boards that support at least 16GB (again, not that you’ll need that much, it’s just a good sign) at speeds of at least 1600MHz for DDR3 and at least 800MHz for DDR2.
6. Expansion slots – Choose a board with at least one PCI Express 2.0 x16 slot or at least two at x8/x8 for dual GPUs, x4 bandwidth is too limiting for a modern GPU. Although there is a benefit to having a x16/x16 setup, the results are not dramatically different from x8/x8.
More Info
More Info 2
7. IGP – Integrated graphics are useful for budget builds and for users who will either not be playing any games, or who will only be playing less intense games at low resolutions and settings. Currently, the best IGPs are AMD’s Radeon HD 3300 and the Radeon HD 4200 (AMD 785G).
8. Form factor – The two most common form factors are ATX (12”x9.6”) and microATX, sometimes denoted as µATX (9.6”x9.6”). In most cases µATX boards will fit in ATX cases, but ATX boards do not fit in µATX cases. µATX boards are sometimes available for cheaper than full-size boards while still retaining many of the features, but they often have fewer expansion slots and can feel somewhat cramped.
9. Rear panel ports – Finally, if you require any extra connectors such as PS/2 or eSata, it’s more convenient if the motherboard already has support for these devices onboard.

RAM/Memory
Memory requires less research than other components, but buying the correct set for your system can be a little tricky at times.
1. Quality – Generally, OCZ, Corsair, G.Skill, and Mushkin make the most reliable sets.
2. Generation – Make sure you pick the right generation of RAM (DDR2/3) for your motherboard.
3. Channels – For LGA 1366 motherboards, low voltage triple channel kits must be used. For LGA 1156 motherboards, look for low voltage dual channel kits. AM3 boards use standard dual channel DDR3, and AM2+ boards utilize dual channel DDR2. Some 775 boards use DDR2, while others use DDR3.
4. Capacity – 4GB is appropriate for most uses. If you are just doing everyday tasks on XP then 2GB will be fine. Contrarily, if you are doing intense RAM hogging activities such as animation on a 64 bit OS and with 64 bit programs, then 8GB would be beneficial.
5. Frequency – While higher frequencies are better, like with many other components, when you start to look at very high speeds, the performance increases tail off, and the price increases take off exponentially.
More Info
6. CAS Latency – The time in clock cycles that pass before a block of data can accessed. Surprisingly, latencies can have as much or more impact on performance as frequencies. Get the lowest latencies that price allows. More Info
7. Voltage – Some boards, such as all socket 1156 and 1366 ones require low voltages to operate safely (1.65V or lower). Also, it is generally best to avoid sticks that require especially high voltages to reach their given frequencies and timings as they can be less stable.
More Info

GPU/Graphics Card
Graphics cards can be very hard to pick out by simply relying on the specifications, so it is best to look at benchmarks and reviews for comparison. Also, as with CPUs, it is often difficult to compare cards from different manufacturers by simply by looking at their specifications.
1. Memory size – This varies between the two camps but generally, 512MB or more is good.
2. Memory type – Only consider GDDR3 or higher.
3. Memory bus size – 128 bit or greater. Although GDDR5 GPUs’ memory bus bandwidth is generally half as wide as those of GDDR3 ones, the GDDR5 cards effectively make up for this by executing twice as much per clock cycle as GDDR3 ones.
4. Memory clock – The speed of the GPU’s onboard memory which, along with the memory bus size, determines the memory bandwidth of the card.
5. Stream processors/Shaders – I’ll use a simple analogy to help clarify what this term means in terms of performance. Essentially stream processors are the number of hoofed animals pulling a wagon (you’ll see why I didn’t just say horses later). At first glance, it would appear that ATI had a huge advantage given their very high numbers of stream processors. This is not exactly true however because Nvidia is using horses while ATI is using ponies. Meaning, while Nvidia cards executes three times per cycle, ATI cards only execute twice per cycle. See number five, to see what this means in terms of performance.
6. Processing Power (TFlops) – A calculation which shows the relative strength of a GPU. To put this into numbers I’ll use the specifications for the ATI’s Radeon HD 4890 and Nvidia’s Geforce GTX 275. To calculate the processing power of each GPU in TFlops, all one must do is multiply the different specifications together.
Executions Per Clock Cycle x Stream Processors x Shader Clock Speed = Processing Power (TFlops)
GTX 275: 3 x 240 x 1404 = 1,010,880 (1.01 TFlops)
HD 4890: 2 x 800 x 850 = 1,360,000 (1.36 TFlops)
More Info
More Info 2
More Info 3
7. Shader clock – How fast the hoofed animals (see number five) are running.
8. Core clock – The speed of the graphics processor on the card. Runs functions at the multiprocessor level, while the shader clock handles the individual stream processors.
9. Transistors – No affect on performance, but does indicates the relative complexity of the chip.
10. Manufacturing Tech (nm) – Like with CPUs, smaller is better in terms of heat production, power consumption, and overclocking capability.
11. 3D API – DX10-11 only. DX11 includes a number of new features including DirectCompute, tessalation, and improved threading.
More Info
12. Power consumption – More power hungry cards will not only run up your electricity bill, but will most likely produce more heat and noise.
More Info

HDD/Hard Drive
Traditional hard drives are fairly straight forward, but there are more factors affecting performance than meet the eye. Also available are Solid State Drives which offer better performance at a high price.
1. Quality – Usually, Western Digital, Samsung, and Seagate make the most reliable drives.
2. RPMs – 7,200 is ideal, 10,000RPM drives are generally not significantly faster than the latest 7,200RPM drives and in some cases can actually be slower (see #3 for explanation).
More Info
3. Platter size – Denser platters are faster and often dense platters make up for lower RPMs and then some. Currently, 500GB platters are the largest in production and these drives offer excellent performance at a good price.
More Info
4. Cache – Mainly serves to prefetch data and write sequence. 16MB or greater is sufficient.
5. SSDs – Solid state drives have several advantages over traditional hard drives. They are faster, use less power, produce less heat, last longer. However all this comes at a high price and capacities are much lower than those of standard hard drives.
More Info

PSU/Power Supply
When choosing a power supply, many people simply look at the total watts, but this is a dangerous practice because many cheaper PSUs do not actually provide the power that they are rated to, are terribly inefficient, and can be a great liability for the rest of your computer.
1. Quality – Before you buy a power supply check for reviews on the websites listed below under more info. Generally, Corsair, Antec, PC Power and Cooling, and Seasonic make the most reliable units, but even with these brands there are exceptions.
More Info
More Info 2
More Info 3
2. Wattage – For onboard graphics and low power GPUs, something in the 400W range will do. 550W is enough to power any single GPU card. For multiple GPU systems, it is best to go with 750W.
More Info
3. Efficiency – only accept power supplies that are 80 Plus Certified, meaning they are guaranteed to use 80% of the power that they draw from the outlet (little wasted power) at 20%, 50%, and 100% load. This ensures that you actually do have enough power for your system and reduces wasted energy.
4. PCI-e connectors – Many modern GPUs require two of these and so, you must purchase a PSU with at least 4 connectors in order to add a second card later, which generally means something in the 750W+ range. However, there are several higher end cards including the 5770 that only require one connector.
5. Active PFC – Never buy a power supply without an Active PFC.
6. Modular cables – Although you often have to pay extra for it, modular cables are helpful in cable management and improving airflow.

Case
A lot of this comes down to preference, but there are a few things to consider.
1. Form factor – In most cases µATX boards will fit in ATX cases, but ATX boards do not fit in µATX cases.
2. Cooling – Cases with at least two 120mm fans are best. One for intaking cold air in the front and another for exhausting it out the back. Additional fans such as one on the side blowing cool air directly onto the components or top fan exhausting heat that has risen up. Larger, slower spinning fans are better because they can move the same amount of air, but produce less noise than smaller, faster ones.
3. Case material – Steel or aluminum cases are best, both have their advantages, but it really amounts to preference. Steel is sturdier and can be quieter, but aluminum is lighter.
4. Size and weight – Keep an eye on the dimensions of the cases you are looking at, some can be surprisingly large and heavy.
5. Windows – Personal preference, some like to look at their components, other people are scared to.

ODD/Optical Disk Drive
Don’t spend too much time on this; just get a cheap, all-in-one SATA burner with good reviews.
1. Speed – Look for a standard 22X DVD+R, 48X CD-ROM burner.
2. Interface – Make sure the burner is SATA, it’s not really for performance reasons, but for easier cable management and better airflow.
3. BD – Blu-Ray drives are growing in popularity and are becoming more affordable.

HSF/Heatsink and Fan
It’s advisable to get an aftermarket HSF if you plan on doing more than a small overclock. It’s often easier to look at a professional review in order to pick the best HSF for your CPU, but here’s a few tips.
1. Core temperature – Look for units that keep CPU temperatures as low as possible.
More Info
More Info 2
More Info 3
2. Fan size – As with case fans, larger slower moving fans are usually best, aim for 120mm.
3. Air Flow – High CFMs mean greater airflow which generally translates into lower temperatures.
4. Noise level – If you want a quiet PC, pay attention to the dBA produced by each cooler.
More Info

TIM/Thermal Paste
Stock HSFs come with a thermal pad already in place and many aftermarket ones come with some paste for you to apply, but in the case that yours doesn’t, or if you plan on doing an extra high overclock, then buy some extra.
More Info

Case Fans
If the LEDs on the fans that often come stock in cases bother you, if you want to purchase some higher end or quieter ones, or if your case doesn’t come with any then buy some low dBA, high CFM ones.

Cable
For some larger cases with bottom mounted PSUs, it is helpful to buy an extender cable to help make your case nice and tidy.

OS/Operating System
Windows 7 64 bit is the best option available, either Home Premium or Professional if you need some of the extra features such as XP Mode.
More Info

Monitors
It may seem that the only important consideration regarding monitors is screen size, however there are several simple specifications that determine quality as well.
Higher resolution monitors require more powerful components to reach the same performance level.
1. Size – The price of LCD monitors is relatively low and therefore it is best to get one that is 20” or larger.
2. Resolution – Higher resolution monitors require more powerful systems, but improve the quality of the image. For example if a 24” monitor has a resolution of 1680x1080, then it has 1,680 pixels measured left to right and 1,080 measured top to bottom. If the same monitor instead has a resolution of 1920x1200 there are more pixels in the same amount of space and therefore the overall size of each individual pixel is smaller, improving the quality of the image.
3. Response time – Lower is better, especially for gaming as slow response times can sometimes result in ghosting or blurring. 5ms or lower is best but with larger monitors response time is generally higher.
3. Contrast ratio – Higher ratios are better this results in darker blacks and more vivid colors. Look for 800:1 or higher.

Keyboard
Some keyboards are ergonomically designed, others have backlit keys, and others have programmable keys. Determine which of these features appeal to you.

Mouse
High DPI mice provide improved accuracy, some prefer wired over wireless, but never get a trackball one.

Speakers/Headset
2.1 speakers are good for low budgets, while 5.1 surround sound setups are more expensive. Also higher total power output (W RMS) and wider frequency responses (Hz) are good indicators of quality. Headsets are also growing in popularity, and offer good value.

Surge Suppressors
Look for a cheap, reliable suppressor with a high joule suppression rating, a good connected equipment warranty, and as many outlets, spaced as far apart from each other as possible.

Other Informative Links
TechReport’s Step by Step Guide to Assembling a Computer
Tom's Hardware
AnandTech
TechReport
TechPowerUp
TheAnimal's Build Advice Form
Shortstuff_mt's Boot Problems Checklist
Tecmo34's Recommended Builds by Usage
Proximon's Guide to Choosing Parts
Skora's If sKora Had Index
Overshocked's Core i7 Overclocking Guide
Smithereen’s CPU Buyer’s Guide 2.0

In case I need to add more later...

nice job

Well done. You may want to add:

1. A HTPC case. OP added it.

2. A link to the Overclocking guide and the Temp guide.

3. There was a post by skora (IIRC) which had a set of builds based on usage (ie Photoshop, WoW,etc)

where is the asus 790xtd?

This is brilliant, this has to be stickied as it will help prevent the same questions asked over and over like (What kind of part do i need for this) on the homebuilt systems forum and will help posters because they won't have to go looking on google everytime for the common parts but will have a quick Link to them from here. Great post

Very nice, and I appreciate the competition!

I had a few minor points... you don't need a 450W for an onboard GPU and most aluminum cases I know of cost more than steel/plastic.

Unless they have fixed some long term issues, you will encounter difficulties editing these long posts. if you find yourself having any difficulties I would suggest doing as I have done, breaking it down into smaller sections.

It will be obvious when you do. Clicking on the submit button will result in an odd error about fields not being complete or some such. My stickied guide, even broken down as it is, is VERY limited. If I add any wording I have to take some away elsewhere.

One more tip I only recently thought of and haven't tried yet... the signature field is limited to so many characters, so it limits the number of links in a sig. We should be able to get around some of this by using TinyUrl.... might even be useful for long posts.

Edit: Yes that works! I fit three links into my sig.

Thanks for the tips Proximon. Good to know about the difficulties involved with long posts ahead of time. Nice thinking about the TinyUrl as well.

Thank you 4ryan6, tecmo34, Shadow703793, and obsidian86 for your helpful suggestions.

Keep the feedback coming!

^Good find on that link. As for the Foxconn sockets, I'm still trying to find the best way to address that issue - any links would be appreciated.

This may help: http://www.anandtech.com/mb/showdoc.aspx?i=3661

http://www.xtremesystems.org/forum [...] c&t=234723

Skimmed through the guide, looks like you put a lot of effort and work into it. Good job. Great guide for the novices I would say.

Good work..

Proximon & jbakerland:

I had this happen just today on my second post in my thread. I had to move some of my info. down to my third post to add what I wanted. It is a good thing you kept a third post open... You could very well need it.

I'd add a link to smithereen's CPU buyer's guide in the CPU section too. Only problem is we now have two buyer's guides in this section.

These guides are build suggestions only people, at some point you will have to use your own brains and make your own decisions! Ryan

GRAMMAR POLICE!!

1. Socket – No affect on performance,

Should read "No effect on performance".

Although your guide is quite comprehensive, I don't think it's as useful as it could be. For example, although you list nearly every factor that one ought to consider when picking out a CPU and that higher is better for this one and lower is better for that one, it still isn't clear which part from your second post to pick because all these parts are worthy of recommendation. I'll leave it to other's to suggest how exactly this could be accomplished. Again, I'm not bashing your post, I'm just trying to help you improve it by pointing out it's weaknesses. Hopefully someone will give a good way to fix this.