Computing for the Bewildered. By Bill Hayles Hello again. THE MECCANO SET THAT IS YOUR COMPUTER - Part 1 I sometimes get e-mails from people who have read in my various scribblings that I build my own computers and suggest others do the same. The gist of the mails is "Oh, but you're a computer expert. I couldn't possibly do anything like that". You know something, they're wrong. OK, I wouldn't suggest to a complete beginner that they build their own, but for anybody who has a bit of experience, and has opened up their computer to install, for example, a new hard disk or a sound card, the leap to building your own from scratch isn't that great. A computer isn't much more than a modern day version of a Meccano set – buts and pieces held together with screws, and connected by cables. Entire books have been written on the subject, so I can't cover everything in a few articles, but in the next coming months I'll try to explain to you what all the various bits are and, in general terms, how you put them all together. Even if you have no intention of actually building your own machine, at least it will give you a better idea of what it consists of and how it all fits together. I am concentrating firstly on the system box. You will, of course need the usual peripherals - keyboard, mouse and monitor, but these are external to the "box" and less intimidating to most, so I'm leaving these until later. All recommendations are personal, and I make no claim to be thorough or scientific. If I recommend something it's because I've used it and have had good experiences with it. This month, we'll go through all the different components, and what they do. We are going to assume you're going to build a normal computer to what's called the ATX form factor. This covers 19 out of 20 desktop computers, and if you're building the twentieth you'll probably know what you're doing anyway! The Case The case is often called the system box, the box, or quite simply "the computer". It's a steel (or, increasingly aluminium) box designed to accommodate all the components you're about to build your computer with. Apart from a few very small "mini" cases, they are all designed round the standard ATX form factor, and for nine out of ten of you, the standard midi tower is what you'll be looking for. Your choice is therefore mainly cosmetic - which case do you think looks best. The more expensive aluminium cases are often easier to work on, and claim to keep the components cooler, but unless you think you're going to work on your computer a lot, or just want something that looks beautiful, the standard steel case will do you. If you want a beautiful but expensive aluminium case, then you can't do better than Lian-Li: http://www.lian-li.com.tw/english/index.php The Power Supply The power supply takes in the 230V mains supply at one end and outputs various voltages, mainly 5V and 12V DC, to the computer components. It's a squarish metal box with loads of leads coming out of it, which connect to the various components in the case. Some cases come with a power supply already installed; for others you need to buy one separately. The most important figure for a power supply is its wattage. For a basic computer you may be able to get away with 250W, but 300W or 350W is a better bet, especially if you think you might add components such as an extra hard disk at a later stage. The power supply is something that off-the-shelf computers often skimp on because, quite frankly, good power supplies are expensive. Respected names in power supplies are Antec http://www.antec-inc.com/pro_powerSupply.html and Enermax (which I use myself) http://www.enermax.com.tw/main.htm The Motherboard (aka the Mainboard) The heart of the computer, insomuch as it's the component that everything else attaches to, the motherboard is one of the most important components and, moreover, one that comes in a huge range of brands, types and prices. It sits on the bottom of your case (as you build it; it will be on the right hand side when you're using a tower case right way up), with various connectors showing out the back, the number and type of connectors depending on your motherboard. So let's try to sort out the wood from the trees. Firstly you have to choose between an Intel or AMD processor (which comes later). Then you have to decide on the maximum combined number of hard disks and CD / DVD drives you're going to need. All motherboards will support four, some will support six or eight, and may also support concepts called RAID and SATA, which are beyond the scope of this article (but you can look up on the web if you're keen). Motherboards may also come with certain facilities built in, such as sound, networking ability and even video. This can save you having to buy a separate sound or network components (“cards”), although you can if you wish. Inbuilt facilities, especially video, are often very basic, and are no substitute for good quality dedicated cards, but may be good enough for starters. Then again, if you intend to buy a special video card, for example, there's no point in paying extra for a motherboard with built-in video. It pays to spend time choosing your motherboard. The two big names in enthusiasts' motherboards are Asus and Gigabyte. I use Gigabyte mainly because I've always used them and know how they work; the reputation of Asus is just as high. http://www.asus.com/ http://www.giga-byte.com/ The Processor (Central Processing Unit, CPU) If the motherboard is the heart of a computer, the CPU is its brain. It's a small wafer, roughly 3cm square, which plugs into a socket in the motherboard. There are only two makes of CPU, Intel and AMD, and there's precious little to choose between them in terms of speed or value. Intel are probably easier to set up for a novice, and can be bought in a package complete with fans; AMD are the choice of "overclockers", or those who try to take their machines to the limit and beyond. I'm not going to tell you which to choose. In any case, you may have already chosen a motherboard and your choice will be dependent on that - motherboards are ALWAYS designed for one or the other - the sockets and much else will be different. Your main choice will be which speed of your chosen CPU you're going to buy - the faster, the more expensive. However, at any given time, the fastest processors will attract a large premium over those only 10% slower, so ask yourself whether you really need the fastest. The CPU is one of the easier components to change on a computer. Currently, (August 2003), the best balance between speed and price seems to be the Intel Pentium 4 2.6GHz or the AMD Athlon XP 2600+. In a few weeks, I have no doubt this will have changed. http://www.intel.com/ http://www.amd.com/ The CPU Cooler (fan) An often neglected or even forgotten component is the fan (or other device) that sits on the CPU and keeps it cool. Modern CPUs generate a lot of heat, and will soon fail if not properly cooled. You can buy CPUs in a box with a basic fan, but your CPU will last longer and be more reliable if you treat it to good cooling. If you want to go the whole hog, you can do what I do and use water cooling – but maybe this is going a bit far for the average user. When it comes to conventional fans then, in general, the bigger the better, but make sure that your fan is compatible with not only your CPU but also your motherboard. Certain motherboards lack the holes necessary to install certain types of fans. Also, there has physically to be room to fit your fan. All in all, this simple component requires a great deal of thought; probably more thought than the CPU it's cooling. If you're not sure, ask your supplier. Respected fan manufacturers are Coolermaster and Thermaltake: http://www.coolermaster.com/ http://www.thermaltake.com/ The Memory (RAM) The type of memory you will need to use will be dictated to you by the motherboard. It will probably be in the form of DIMMs (Dual In-Line Memory Modules) which slot into appropriate slots in the motherboard. What you are able to choose is the quantity (the number of megabytes) and, to a lesser extent, the speed. As to the quantity, the more the merrier; you can't have too much RAM. For an average system, aim at 512Mb, but if you can afford it go for 1Mb or even more. You may need to buy two memory “sticks” to make up the required quantity. Try not to fill all the RAM slots unless you never plan on adding more later. As to speed, try to match the speed of the RAM with that specified in your motherboard handbook. Faster RAM will work fine at a slower speed (but will be a waste of money) but slower rated RAM will simply fail in a faster motherboard. There are many RAM brands. Unless you intend to push your computer to the limits, there's no need to go with expensive, branded RAM. Ask your supplier for his recommended generic (unbranded) RAM. That's enough for one month. We still have to look at the peripherals that plug into the motherboard (the “cards”) and those that are connected by cables (mainly disks), and then we can start looking at how it all fits together. http://cftb.net is the Computing for the Bewildered web site, with everything I produce for my classes, these columns and other material available for download. If you have been, thanks for reading this.