10 important things to check when buying a computer
Buying a computer is not so easy for "non-techies", the main problem with common people is that they don't know what they really need. If you are planning to read e-mails and surf the web, you will not buy the same computer your hardcore-gamer neighbour has.
Processor is the heart of your computer. Your processor needs are based on what you are planning to do on your new computer. If your main purpouse is using it for internet, e-mail, word processors and office applications, any modern processor in the market will fit your needs. One important thing to look in a processor is clock frequency (which determines your processor speed), now this is measured in Ghz. But don't be fooled by checking only processor's clock frequency, one thing more to check in modern processors is the number of cores. Today processors have more than one core, this is important for multihreading (doing more than one task at the same time), usually processors whith more than one core have less clock frequency but they still are more powerful. A processor can have one, two, four, ... cores and every core can act as a standalone procesor.
Hard disk prices grow in terms of space and speed. Go for the one that you need most, if you are planning to build a media server to stream MP3s over your network then, for sure the most important thing is to buy a big disk to fit your 1 Terabyte music collection, but if you are planning to stream High Definition videos you will also need a fast hard disk with a high transfer rate. There's no trick to check disk space (if mega, giga, and terabytes are words you know, if not you can check it on Wikipedia). Things to check for a high transfer rate are connection, IDE (the old one), ATA and SATA (Serial ATA, wich is the latest and even fastest), also RPM determines how fast your disk is turning and, of course, this will affect your disk speed.
Is screen important for you? If not, maybe you can skip these and next two ones, you can jump direct to Operating system. However screen is an important thing for games, graphics, watching movies ... Things to check when buying a screen are: aspect ratio, usually 4:3 or 16:9, the last one will give you a panoramic view and a more modern interface. Modern games now usually support 16:9 aspect ratio. Full HD or HD? This will determine your screen resolution, Full HD (also known as 1080p) works with 1080 lines of resolution with progressive scan which gives you the best reolution (1920x1080), HD (also known as 720p) works with 720 lines and give you a not so good resolution (1280x720). If you buy an HD screen 1080p or 720p, check that it has an HDMI connection in order to plug it to your computer in the best way.
This is an interesting piece for games. Check your video graphics card connectivity, look for an HDMI connection (modern connection for HD video) but you can also look for VGA, DVI connections if you pretend to use it also with older screens, you can also check for firewire if you want to capture video or TV connection if you need it. Video cards have a built-in processor which is called GPU (Graphics Processor Unit) this is one of the main things to check in your new video card, GPU model, speed, ... and the other important thing is Video memory, you have to check the size of video memory (usually from 64 MB to 4 GB) and the speed of this video memory.
An important characteristic of sound cards is polyphony, which is more than one distinct voice or sound playable simultaneously and independently, and the number of simultaneous channels. These are intended as the number of distinct electrical audio outputs, which may correspond to a speaker configuration such as 2.0 (stereo), 2.1 (stereo and subwoofer), 5.1 etc. You have to check that your card supports Dolby Digital Surround, which provides surround sound (usually called 5.1), where you can plug a set of five speakers and a subwoofer.
Operating system is an important thing when buying a computer, it's not the most important but for many people it's decisive. If you want to play, run Microsoft applications, Office, ... then go for Microsoft Windows operating system. If you like rock solid computers, using your computer for those internet things, a cool and cheap operating system and you like to do things on your own (as you don't need technical support) go and get a Linux. If you need commercial technical support and assistance but still need a rock solid OS go and check Mac OSx and forget all other aspects in this hub you are in a different world, that is what I call Apple's world.
RAM stands for Random Access Memory and it's a very important thing to check in your new computer as low memory can produce bottlenecks also in your home computing. Modern operating systems and games are resource-hungry in terms of memory. However for most people 4 Gb will be enough nowadays. There are many types of technology in RAM modules: SDR or SDRAM is the latest one (maybe you will not find these on your shop), then arrived DDR, DDR2, and DDR3 (latest) everyone performs faster and better than the older one. There is also RDRAM (Rambus DRAM), which is a high end product only used in high-tech computers and your Playstation 3. You can also check clock frequency to have an idea of memory DIMMs speed (usually in Mhz).
Network card is your door to networking, internet. The most important thing to look in a network card (for non-techies) is the network speed, 10/100/1000 Mbps. A card with 10/100/1000 can connect to gigabit network using a speed of 1000 Mbps. The fastest nowadays (and perfect for HD video streaming, realtime applications and heavy traffic networks, usually not like yours).
Network card is not the only connectivity to check in a computer, as modern computers offer also wifi (wireless network) connections, bluetooth (check that is Bluletooth 2.0, the last one), infrared connections. You can also look for serial and parallel connections (for specific needs), how many USB ports your new computer will have. Look for an HDMI connection for conneting your HD screen, DVI and VGA are old connections, but it can help you to connect with older screens, this will be more important on laptops or netbooks.
Do you plan to use your computer mainly at home, then go for a desktop computer. You plan to store your movie and music collection, and stream it all over your home then go for a server computer that fits your needs. You need lots of power, but you need to take your computer with you sometimes then go for a laptop. You need an "always with you" computer to stay connected, check your e-mail, surf the web and a little word processing and office tasks then go for a netbook.
Predicting the Computer of 2004 in 1954
Buying a computer today is not so difficult, computers are not so complex.