IEEE 1284 Parallel Port
The parallel port was primarily used to connect a printer to a PC. Today, the parallel port is obsolete, being replaced by the USB port. Although now obsolete, millions of parallel port printers were manufactured and no doubt many of them are still in use today. I'll briefly describe the it in this article because you may run into a question about it in the CompTIA A+ Certification Exam. More ...
Understanding Modern PC Specifications
There is a huge variety of different PCs available out there. Its no wonder that consumers are confused about what to buy. This article explains modern PC specifications. More ...
PC Video
The video circuits of a computer take digital data and arrange it for display on a screen. In the past, PCs used CRTs (Cathode Ray Tubes) for video display. Today's PCs use LCDs (Liguid Crystal Displays). Whether the display is CRT or LCD, the image is created with a matrix of dots (called pixels for picture elements). More ...
PC Motherboard Expansion Cards
The expansion slots available on motherboards allow for a variety of upgrades in a computer system, but matching the appropriate card to an available slot needs to be addressed before making any purchasing decisions. The most common types of expansion cards for modern computer systems can be broken down into three formats: PCI, AGP, and PCI Express. More ...
The Master Boot Record (MBR)
The Master Boot Record, created when you create the first partition on the hard disk, is probably the most important data structure on the disk. It is the first sector on every disk. The location is always track (cylinder) 0, side (head) 0, and sector 1. More ...
Hard Drives - ATA versus SATA
with data rates hitting the 133MB / sec mark the parallel ATA standard is maxing out, thus industry leaders got together and came up with a new standard known as Serial ATA (SATA). More ...
Power Supply Form Factors
The shape and physical layout of a power supply is called its 'form factor'. Power supplies come in several industry standard form factors. Power supplies with the same form factor are physically interchangeable. More ...
Hardware Resources Explained
Hardware devices, such as modems, network circuits, sound circuits, and so on, require system resources such as Interrupt Request (IRQ) lines, Input/Output Port (I/O) addresses, Direct Memory Access Channels (DMA), and a range of Memory Addresses for storing code and data. Each device needs its own set of resources. If two devices attempt to use the same resource, your system may lock up or crash. More ...
PC Keyboards
Today, there are many keyboard variations. Some keyboards have an integrated pointing device such as a trackball. Ergonomic keyboards are designed to be more comfortable for the hands and wrists. Regards of the variations, all keyboards, except those on notebook computers, follow the 105-key standard. More ...
Buffered, Unbuffered, Registered Memory, What is the Difference?
Buffered and Registered memory are the same thing. The buffer is a register that resides between the system's memory controller and the RAM. The buffer is often, but not always, used to provide ECC (Error Checking and Correction). More ...
Hard Disk Drive Basics
On a hard disk, data is stored in thin, concentric bands. A drive head, while in one position can read or write a circular ring, or band called a track. There can be more than a thousand tracks on a 3.5-inch hard disk. More ...
How Does the CPU Cache Work?
CPU's however use a 2 level cache system. The principles are the same. The level 1 cache is the fastest and smallest memory, level 2 cache is larger and slightly slower but still smaller and faster than the main memory. More ...
What is USB OTG?
USB is wonderful because it allows you to connect and disconnect devices from the computer without rebooting the computer. However, wouldn't it be even more wonderful if two USB devices, like a digital camera and a storage device could connect to each other directly? That's what USB On-The-Go (OTG) does. More ...
Anatomy of a Hard Drive
A hard drive contains a spinning metal disk. The surfaces of the disk have a magnetizable coating. An actuator arm with a read/write head on its end is passed over the surface of the spinning disk. More ...
