How to: Choose the Parts for a Custom PC

So many choices, what to choose?

People build their own PC, rather than buying off the shelf, for many reasons. One may be just to save money, and another may be that no mass-marketed computers really appeals to you or suit your needs. Whatever the reasons, when you are just starting to plan a PC build, it is essential that you don’t panic and that you remember to ask for help. The internet is full of forums, like our very own, where people sit happily at a PC waiting to answer your questions instead of doing their day jobs. Once you get a basic understanding of the concepts, the whole process will seem a lot less scary, and you will find that building a computer can be quite easy and a lot of fun. The first of our as yet undetermined part series on PC hardware is an introduction to building a great gaming rig. This guide should set you in the right direction for your first build. Tune in over the coming weeks to see an in depth look at every component to help you make even more informed decisions for your build.

CPU:

We will start off with the processing center of the PC, the central processing unit (CPU). In the past, clock frequency was essential in choosing a CPU. Today, the best thing to do when choosing a CPU is to ignore its frequency. The architectures in CPUs are so different—even between processors made by the same company—that a high frequency does not always correlate with increased speed. Instead, a great way to see how fast a CPU is, is to look at benchmarks.

When choosing a CPU, make a list of all the programs you currently use. If you only do basic tasks such as web browsing, word processing, and instant messaging, a cheap dual core CPU will be great at all those tasks. If you play high end games, as you most likely do, a faster dual core will be essential. While today’s games do take advantage of multithreading, we are not to the point where four cores are two times better than two cores at the same clock speeds. Most games are still primarily dependent on the graphics card; a great way to stretch your budget is to buy a dual core, and spend the extra money on the video card. If your PC usage stretches into the land of heavy video encoding or RAW image processing, a quad core will really help. These tasks will often utilize as many threads as your machine is capable of and are extremely CPU dependent. A higher performance CPU will provide great benefits in multimedia encoding applications. Additionally, consider searching the internet to identify any specific applications you use often are multi-threaded. If a specific app is optimized for multi-threaded processing, then a quad core will show its muscle.

Finally, another important factor for consideration when buying a CPU is overclockability. Often, with the right complimentary components, inexpensive processors can overclock to double their rated frequency. If overclocking interests you, it can be a great way to stretch an inexpensive part to the performance level of one that costs four times as much, just remember to do your research before attempting anything drastic. Unless you are buying an Intel Extreme Edition CPU, or an AMD black series, the core multiplier will be locked, so you will be forced to overclock by bus speed, or base clock, and your motherboard selection will be a huge limiting factor.

Cooling:

Unless you are buying an OEM processor (online retailers generally make this clear by stating ‘OEM’ in the title), your CPU should already come with a stock cooler. This stock cooler is generally fine; if you are going to run at stock frequency, or if you are going to do a mild overclock, it will keep your processor at reliable temperatures. Anything more aggressive will require more aggressive cooling, especially when you increase the core voltage of the processor during the overclocking process. It is essentially impossible to tell how effective a third party cooling solution is just by looking at it, so once again do your research. Look for heatsink reviews that use controlled heat sources, rather than actual processors, as these will have the most consistent results between heatsink models. Make sure, before you buy, that the cooler will fit on the motherboard (some are so big that they block other components) and inside your case (height can be an issue). Water-cooling should be considered if you want a more quiet setup, or you are doing such heavy overclocking that air cooling just isn’t enough. Be careful when buying a water cooling setup however, low-end water cooling is generally less effective, louder, and much more expensive than good air cooling. A third technology to consider is thermoelectric cooling (Peltier cooling); this kind of cooling varies greatly depending on cost. Expensive versions are very effective and can keep the CPU below ambient air temperature, while less expensive models are similar in effectiveness to water-cooling with the advantage of being more self-contained, and a lot easier to install.

Motherboard:

Choosing a motherboard can be nerve-racking, you must make sure that it has all of the features you need, and all of the other components will be compatible with it. Additionally, you want to get a high quality board that will last a long time. Luckily, choosing the right motherboard is not that difficult of a process. The performance difference between a low end motherboard and a higher end one based on the same chipset will only be about 5%, so what justifies a higher end one? For one, higher end motherboards will be better laid out, so that even with everything installed, the headers and ports will still easily accessible. A second important feature of high end MB’s are solid capacitors. Capacitors that do not use solid dielectric material can fail early and cause seemingly random PC behavior such as crashes. Furthermore, high end boards will be easier to overclock, and they will have features such as SLi or Crossfire compatibility. Additional features that may be of importance depending on your needs are IEEE 1394 (Firewire), dual LAN connections, parallel ATA support, and/or a RAID controller.

When identifying the right motherboard, it is also important to consider the case that will be used. For example, an ATX motherboard won’t fit in a BTX case. However, presently (BTX is less popular today) the only real choice is between ATX and Micro-ATX. If keeping the size of the PC small is one of your goals, and you won’t be adding many expansion cards, Micro-ATX can be great. If you need more expansion cards or size just is not a factor, then go with ATX. Micro-ATX boards will fit in a larger ATX case though, just not the other way around. There are other form factors, such as mini-itx, which are used in very small computers. These boards don’t make great gaming PC’s because they generally do not have a PCIe x16 graphics card slot.

On last thing to look for when selecting a motherboard is the placement of the SATA ports. If you select a extra long video card, make sure that you confirm that enough SATA ports will be exposed for the number of hard drives you need, or that you select a board with right angle connector so that the video card won’t be blocking the SATA ports. Sometimes you can even use right angle adapters on the ends of traditional SATA cables to combat this issue.

RAM:

When buying RAM capacity is one of the major things to think about. 32-bit operating systems only have 4GB of memory address space, and the OS will only see 3.25GB of RAM on average depending on the other components you can in your computer. If you are planning to run a 32-bit operating system, there is no point getting more than 4GB of RAM, and you should consider 64-bit OS with a new PC build, because it will be more stable and allow you to access all the memory. It may seem like 4GB is overkill, given that just a few years ago 1GB was considered plenty, but it is certainly not. Newer applications always use a lot more RAM then older ones, and new operating systems like Vista are optimized to make more efficient use of memory. Vista will use free memory as a cache, allowing programs to access it if they want to, but also storing information there about frequently used programs that are not currently running.

Motherboards will usually only accept one type of RAM, so select RAM that will be supported by the motherboard. The two commons types are DDR2 and DDR3. RAM frequency and latency are also important, although not as much as they once were. Performance gains from high speed and low latency memory are generally only seen in benchmarks. If you are planning to overclock, select memory that has a heat spreader built in. Although, it is possible, and often advisable, to use a memory divider when overclocking to keep your RAM at its recommended speed. Motherboard configure RAM in either dual channel or tri-channel, and it is important to use those features to increase performance. The paired or grouped channels are generally the same color on motherboards, so when you add RAM, make sure you add enough that it will fill all the slots of the same color.

Video Card:

The graphics processing unit (GPU) is the most important component if you wish to play the latest 3D games. When you are looking for a video card, first you want to see what games you play, and what resolution you are playing them at. If you play only older games (from 2006 or earlier), or if you play only at a lower resolution, then a high end video card will be overkill. In the current PC hardware market, the high end enthusiasts cards are really only necessary for resolutions at or above 1920×1080. At 1680×1050 or below, the cards just below the flagship models will work effectively.

A single card will usually provide better performance for the price than multiple cards in SLi or Crossfire. The best time to use multiple cards is if the fastest single GPU just isn’t fast enough for you. Generally this only happens if you are using a 2560×1600 resolution and do not want to game at anything below that. If you are buying a video card the size of the frame buffer (RAM) should not be used to identify the fastest card. Be sure to read benchmarks to see the true speed of the video card. Often you can search for benchmarks of a specific graphics card with a specific game at specific resolutions. This can be a great way to make sure the card you like will be the best one for the game or games you play the most.

Power Supply:

The power supply (PSU) is often overlooked, especially by people working on their first PC build. In general, never use a power supply bundled with a case. Just look for the same case without a power supply, and buy a separate power supply from a reputable brand. Remember that most computer components don’t really need that much power, so when you are choosing the right wattage, it is a good idea to go online to a power supply calculator (like this one.) and see how many watts your prospective computer actually needs. Just remember, you do not want to run a power supply too close to its rated maximum, as it will reduce its lifespan and generate extra heat. A good minimum in today’s market for gaming PC’s is a power supply rated at 500W. Finally, confirm that the power supply has all of the outputs needed to run every component in the PC, specifically confirm that it has the correct 6-pin and/or 8-pin PCIe connectors for your graphics card.

Hard Drive:

The most important things to consider when selecting a hard disk drive (HDD) is whether you want to spend the money on capacity or speed. Most high capacity drives spin at 7200rpm, while a high speed drive will spin at 10000rpm or will be a solid state (flash) drive. Again, the way to find the part with the best performance is to find benchmarks. Transfer speed, given in megabytes per second (MB/s), and seek time, given in milliseconds (ms), essentially tell you how quickly large files will transfer and how quickly files will be located on the drive (respectively). Fast transfer speeds mean that you will be able to load the operating system faster as well as being able to transfer large files faster between hard drives. Low seek time will help when attempting to load many files from many different locations on the disk.

Luckily in the hard drive market you can have your cake and eat it too. For speed and capacity, you can use RAID. RAID is an acronym for redundant array of independent (or inexpensive) drives (or disks). Basically, you combine multiple drives and get some combination of increased speed capacity or data security depending on the type of RAID. The most common RAID types are RAID 0, 1, 5, and 10 (also known as 0+1). RAID 0 is not in fact redundant at all, and is most commonly used for raw speed. RAID 0 combines two or more identical drivers and you split the data between them, make writing and reading a lot faster, theoretically twice as fast. The other RAID options are generally used in server configurations, and aren’t of much interest to gamers. Just remember to back up your data if you use RAID 0. Because you use two drives, instead of just one, there is double the chance that a drive will fail, and with RAID 0 if one drive fails the data on the second drive is useless.

Optical Drive:

Optical Drives are probably the easiest component to select. In general any drive that reads and writes CD and DVD media and uses the SATA interface will be sufficient. You might want to just look at the ratings of past purchasers to identify the best on. Unless you plan on watching Blu Ray movies on your PC, there is little reason to get a Blu Ray drive. BluRay writable drives and media are still way over priced. Additionally, Lightscribe drive (that create images on the label side of a disc) are intriguing, more expensive Lightscribe discs are needed, and the process is very slow.

Computer Case:

When you are picking out a computer case, important things to consider are ease of use, how it looks, and how well it dampens the noise of fans, hard drives, and other moving parts. More expensive computer cases will have tool-less bays, which mean that you can add drives or expansion cards easily without having to take out a screwdriver. The number of fans is also important to consider. Many high speed fans may seem better for cooling, but they can be very loud. One option is to purchase a fan speed controller that goes in a 5.25″ bay. This will allow you to dial in the fan speed that best combines cooling and noise performance. Finally, the case is the only part of your PC that you really look at, so pick an attractive one that you won’t mind looking at for the next couple years.

Conclusion:

What’s the next step in building a computer? Buying it and building it of course! Don’t worry if you are having trouble finding components to put in your build, there are plenty of forums (like ours.) full of people more than happy to help you. When you are posting on a forum be sure to include your budget, what you plan to do with your PC, and what resolution you play games at. To get the best deals, it is important to buy at an online stores, and also be open-minded. When you are trying to get the best performance for a price, brand loyalty is a bad thing. Don’t buy a product just because it’s produced by a certain company. Once you do have the components, don’t throw the boxes away, in case the product breaks within the warranty, you will still need it to ship back to the manufacturer.

Happy building!