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Personal Computer Evolution

The personal computer evolution can trace its roots back to KENBAK-1, which only could be considered an educational trainer.  Some people consider the MITS Altair 8800 the personal computer, it was more advanced then then KENBAK-1.  The PC slowly evolved into the 8-Bit CPM machines, and few other proprietary platforms like the Apple II series, Commodore 64, Atari 400/800, and several other model target at education and consumer markets. 

In the early 1980 IBM created the original IBM PC, it was first real business computer and soon became the industry standard.  The Apple Macintosh was released a few years later, it never gained the popularity of the IBM PC, and all its variants and clones.  The clones eventually crushed IBM market share, and amazingly enough the industry still managed to evolved.

The fastest and most modern PC still has hardware architecture roots that can be traced back to the original IBM PC.  For example, most modern still have BIOS that has legacy code is probably a few decades old.  Although there is one piece of hardware on the modern PC that has never evolved, it the power cable.  You could use the same power cable on an original or modern PC.

Case Form-factor
  • Desktop: The a long rectangular desktop case that laid flat on the desk was the original IBM PC form factor.
  • Tower: The a long rectangular desktop case evolved to stand on its side so could be placed on the floor instead of using a lot of desk space.


It seems like every decade or more, the processor architecture doubles, to handle more memory or data processing.  With 4GB of memory becoming standard on most desktops, 64-bit versions of the OS are being pushed to the forefront.
  • 16-Bit (Single Core) (Obsolete): The orginal IBM PC (and clones) used the Intel 8086 and 8086 CPUs
  • 32-Bit (Single Core) (Obsolete): The Intel 80386, was the first major shift from a 16-Bit OS/Hardware architecture to 32-Bit.
  • 64-Bit (Single Core) (Obsolete): 2003 AMD released x86 32/64-bit hybrid CPU architecture (know AS), that later got adapted by Intel (branded as EM64T).
  • 32-Bit (Multi-Core): In 2006 Intel released the Core Duo first x86 dual-core CPU.
  • 64-Bit (Multi-Core): In 2007 AMD released the Athlon 64 X2 first x64 dual-core CPU.

For the last few decades, RAM storage and speed has progressively increased, and showing no sign of slowing up.  Modern operating systems and application consuming more and more of this resource.


Interface Expansion Card Slots
The expansion card is a printed circuit board that can be inserted into an expansion slot of a computer's motherboard to add functionality to a computer system.
  • ISA 8-Bit (Obsolete): A computer bus standard for IBM compatible computers introduced with the IBM PC.
  • ISA 16-Bit (Obsolete): A computer bus standard for IBM compatible computers introduced with the IBM AT.
  • EISA (Obsolete): ISA bus was extended for use with 32-bit processors.
  • VESA Local Bus (Obsolete): Worked with the ISA bus; it acted as a high-speed conduit for memory-mapped I/O and DMA, while the ISA bus handled interrupts and port-mapped I/O.
  • MCA (Obsolete):A proprietary 16- or 32-bit parallel computer bus created by IBM in the 1980s for use on their new PS/2 computers.
  • PCI (Obsolete): A computer bus for attaching hardware devices in a computer.
  • APG (Obsolete): A high-speed point-to-point channel for attaching a video card to a computer's motherboard, primarily to assist in the acceleration of 3D computer graphics.
  • PCI Express: A computer expansion card standard designed to replace the older PCI, PCI-X, and AGP bus standards.

Motherboard Form-Factors
There are several motherboard form-factors that are available and not listed here.  Although these were and are most popular available.
  • XT (Obsolete)
  • AT (Obsolete)
  • Standard-ATX
  • Micro-ATX
  • Mini-ITX
  • Nano-ITX
  • Pico-ITX

Sound Card
Sound card technology has advanced over the years advanced from being analog mono, stereo 2.0, 2.1, and 5.1, to all digital from the computer to amplifier (then converted into analog).  Most modern sound card technology is handled by the motherboard.  Although, gamers and audiophiles will generally get a dedicated sound board.  Below is a list of previous and current standards.

Video Cards
Video card didn't start taking off until PC games like DOOM required more and more processor speed.  The early PCs, required dedicated video card, then that basic functional became apart of the motherboard, like sound.  Although as the realism of games increased so did the processing requirements to displaying 3D photo-realistic environments.
  • Simple Graphic Card (e.g CGA, EGA, and VGA)
  • Dedicated Graphic Card with GPU and RAM (from companies like ATI and Nvidia)
  • Multiple Dedicated Graphic Card (e.g. SLI and Crossfire)

Computer Power Supplies
The original IBM PC came with an 80-watt power supply.  Modern computers can come with power supplies that can use 1-kilowatt (or 1000 watts) of power or more.  There has not been a lot of advancement in this component of the modern PC. Most power supply still convert AC power from the wall to DC power for the different components in the system. The largest improvements in power supplies has been in efficiency, and power output.

Computer Storage Devices
The original IBM PC supported a cassette port or one or two 360KB floppy drives.  It was not until the IBM XT that hard drives were offered.  Like RAM for the last few decades, computer data storage capacity and performance has progressively increased, and showing no sign of slowing up.  Modern operating systems and application consume more and more of this resource as its made available.
  • Cassette (Obsolete)
  • Floppy Drive (Obsolete)
    • 360KB 5.25" Full High (originally available on IBM PC and XT)
    • 360KB 5.25" Half High (originally available on IBM XT)
    • 1.2MB 5.25" Half High (originally available on IBM AT)
    • 1.4.MB 3.25" half High
  • MFM Interface (Obsolete)
    • Hard Drives (5.25" Full High) (originally available on IBM XT)
    • Hard Drives (5.25" Half High)
  • PATA (IDE) Interface (Obsolete)
    • Hard Drives (5.25" Half High)
    • Hard Drives (3.5" Half High)
    • Hard Drives (2.5" Half High) (primarily used in small form-factor cases and portable computers)
    • Optical Drives (CD, DVD)
  • SATA Interface
    • Hard Drives (3.5" Half High)
    • Hard Drives (2.5" Half High) (primarily used in small form-factor cases and portable computers)
    • Optical Drives (CD, DVD, Blu-Ray)
    • SATA SSD (3.5" Half High)
    • SSD (2.5" Half High) (primarily used in small form-factor cases and portable computers)

Other storage technology worth noting which are used on higher-end systems are:
  • SCSI Interface: One set of electrical connections stretching from one end of the SCSI bus to the other. A SCSI device attaches to the bus but does not interrupt it.
  • SAS Interface: A point-to-point serial protocol that replaces the parallel SCSI bus technology that first appeared in the mid 1980s in data centers and workstations, and it uses the standard SCSI command set.
  • RAID (Redundant Array of Independent Disks): A technology that provides increased storage functions and reliability through redundancy.  This is achieved by combining multiple disk drive components into a logical unit, where data is distributed across the drives in one of several ways called "RAID levels"

Computer Monitor
The original IBM PCs supported a single monochrome or 16 color CRT display.  Most modern computers can use one, two or more LCD or LED monitors.  Modern displays are able to display high resolution photo-realistic color images and video.  The LCD and LED technologies are also more power efficient then the older CRT monitors, and are a lot thinner.
  • CRT (Obsolete) - Single Monitor Configuration
  • CRT (Obsolete) - Multiple Monitor Configuration
  • LCD - Multiple Monitor Configuration
  • LED - Multiple Monitor Configuration

Device Cooling
On the early PC, the cooling requirements were pretty minimal, but as PC grew in speed the cooling requirements increased.  Most modern PC still use passive cooling technologies, such as: heat sinks and pipes.  Faster computers can use more exotic active technologies such as: liquid or piezoelectric

  • Passive
    • Heat-sinks/Heat-pipes: Conducts heat away from the computer components (e.g. CPU, GPU, RAM, etc.) by using a heat-conductive metal (generally aluminum or copper); sometimes in combination with heat pipes.  Then commonly uses air to cool the components.
  • Active
    • Fans: The most common, simplest, and most inexpensive form of cooling used for moving air over a computer components (e.g. CPU, GPU, etc.) or off of heat-sinks and heat-pipes.
    • Liquid: a heat sink designed to use water instead of air. It is mounted on computer components (e.g. CPU, GPU, etc.). Water is pumped through the water block, transferring the heat into the water, which is then usually cooled in a radiator.
    • Peltier or Thermoelectric Cooling: These forms for generally the most complex to install, and manage because of condensation that can build up.  Although they are one of the better forms of extreme cooling for overclocking without using liquid submersion.

Human Input Devices
The original IBM PCs came with keyboard for user input.  This later evolved into mechanical and laser mice, and now people are experimenting with camera technologies like Microsoft Kinect.
  • Keyboard: Probably one of the oldest pieces of technology on a modern computer that is still used. It has evolved a little since its early creation for use in typewriters, but its still basically the same.
  • Mechanical mouse (Obsolete): Developed in the 1960 by Douglas Engelbart, it allowed computers to be controlled in a new way, which led to the creation of the GUI (Graphical User Interface).
  • Trackball: Basically its mechanical mouse turned upside down.  Instead of moving the ball on a hard surface, you move it with your hands.
  • Laser mouse: Detects movement mouse movement by bouncing a light off a physical surface, and reading back its direction and how fast its moving.
  • Webcam: A video camera that feeds images in real time to a computer or network, often via USB, Ethernet or Wi-Fi.

Computer Networking
The original IBM PC, had limited data communication abilities.  You could have used an analog modem to communicate with another computer, or another service that supported this technology like a BBS.  Today, data communications comes in several forms, from wired to wireless to fiber optics.  The most popular forms of data communication is wired Ethernet, or wireless 802.11 networks.  Although most home and business computers don't use fiber optics, its primarily used by large enterprises and governments.

Computer Speakers
The original IBM PC, came with a single speaker that could make a few beeping sounds.  In comparison to other PC technologies, speakers have not advanced that much over the decades.  The quality of the sound has improved, and some minor advancements in the overall technology (for example: surround sound) have occurred but it has been limited.
  • Mono
  • Stereo 2.0
  • Stereo 2.1
  • Stereo 5.1 (surround sound)

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