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.
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.
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.
There are several motherboard form-factors that are available and not listed here. Although these were and are most popular available.
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 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.
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.
Other storage technology worth noting which are used on higher-end systems are:
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.
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
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.
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.
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.
As personal computers have been upgraded to deal with larger resources, so have other computing technologies evolved to handle new advancements: