Data In, Data Out
Thinking Inside the Box
by Bill O’Kane, Alternative Business Systems
This brings us to the most important part, the box itself. As mentioned earlier this is commonly referred to as the CPU, and nobody will rap your knuckles for using the term. Referring to it as the system unit certainly does not seem to do it justice, as this is the actual computer, the heart, mind and soul of the machine. Everything that attaches to the computer is nothing without it.
Everything in your computer goes through the mother board or system board. The motherboard contains the RAM, CPU, connectors for the power supply, drives, and slots for expansion cards. The most common slots you will see today are PCI and AGP. In some cases the motherboard contains built-in video, sound, modem, or network capabilities. In other cases special boards plug into these slots allowing for these capabilities. Your machine may have ISA (black) slots but these have been replaced by PCI on modern machines although some manufacturers include them for compatibility sake.
PCI connectors are usually white and can take many types of cards such as video, sound, modems, or network. AGP connectors, which are usually brown, are specific to video. These expansion boards allow you to upgrade your computer quite effortlessly by improving sound hardware, video, etc.
For the average user the cards include or built in are quite sufficient. If you are doing sound, video, or graphics editing, you will want to be able to upgrade your cards to keep up with the changing environment. Gamers will certainly want to have AGP video expansion available as games are quite video intense and require the extra speed AGP and high-end video cards provide.
Inside this box is where the magic takes place. The electronics inside a computer are very complex, made up of millions of circuits, all working in harmony and on a very precise clock to allow data to move and be processed with incredible precision. Modern computers are capable of doing billions of calculations per second. To put this in perspective, modern personal computers have more processing power than all the computers used by NASA to put a man on the moon. Imagine having all that power at your fingertips!
At the heart of it all is the CPU or processor. It controls all the processes inside the machine. The most common names in processor manufacture are AMD and Intel who make up the vast percentage of CPUs found in personal computers. The processors themselves are more commonly known by their model names such as Pentium, Celeron, Athlon, and Duron.
The CPU is in charge of not only processing its own data but redirecting data to things like the video card or sound card if processing is to be done on these cards. CPU speeds are measured in MHz or millions of cycles per second, representing the clock speed of the processor and although there is much discussion of the merit of this form of comparison, for general usage the more MHz, the more horsepower the chip has.
There are many things that affect the overall speed of the computer but are far outside the scope of this article. Clock speed is important because data moving in the computer does not move in a smooth stream but on ticks of the processor clock.
Another important term you will hear is RAM or just memory. RAM stands for Random Access Memory and is easily accessible and fast storage used by the system for data that is being used at the moment. The important thing to remember is that RAM is volatile, meaning it is erased when the power is switched off. The computer must constantly send small voltages to the memory chips to keep their data intact.
The circuitry in RAM is laid out in grids allowing the computer to give an address similar to a street address to every bit making it easy to find when it is needed. The amount of storage in a RAM chip is measured in bytes, with 1 Kilobyte being approximately 1000 bytes and exactly 1024 bytes. This discrepancy has to do with the way binary numbers work and is also outside the scope of this article.
Knowing Kilo represents one thousand, Mega represents one million and Giga represents one billion is accurate enough for most users. Understanding bits and bytes is not necessary for the successful operation of your computer but as a matter of interest there are 8 bits in a byte, a bit being a single binary digit. Why eight bits to a byte, why 12 eggs to a dozen, someone smarter than me decided that is the way it should be. Most modern systems require at least 128 Megabytes of RAM to operate comfortably but increasing the RAM can improve performance.
We have taken the data in, processed it, sent it back out, but what if we want to store it? Next we will look at disk storage devices. If you have any questions or comments, please feel free to contact me. I will be happy to help you.
Contact Bill O’Kane at: Alternative Business Systems
680 Water Street
Miramichi, New Brunswick
E1N 4B8 Canada