Computers Exposed

From left to right:

Top row: 6x86MX PR233, Intel Celeron, AM486 DX2-66, Intel i486 SX.

Middle row: AMD Sempron, Intel Pentium (pin side up so that you can see the huge number of connections), Intel Pentium (top side), Intel Pentium (a different version).

Bottom row: Intel Pentium III, AMD Athlon 64 X2, Intel Pentium 4

Don't worry if any of the above doesn't mean anything to you. These CPU's were used in computers from about late 80's to 2000. The older CPUs (such as the Intel i486) were larger and heavier than the newer CPUs (such as the Intel Pentium 4). So, even as the CPUs got smaller and lighter they still got more powerful and faster. An important thing to remember is that actual chip that contains the circuit (as seen at the top of the CPU) is much smaller than the package but because there are so many connections the package has to be much bigger than the actual chip for all the pins to fit on.

Because these CPUs contain millions of tiny transistor switches that turn on and off at high speed a considerable amount of heat is generated when the CPU is in use. This heat can have a bad effect on the CPU and even cause it harm. To help safely remove the heat, a large piece of metal know as a heatsink is attached to the top of the CPU using heat conductive paste (the white stuff seen on one of the CPUs in the photo above). Especially with the newer CPUs, however, a fan is used in addition to the heatsink (usually fixed on the heatsink) to remove the heat quickly and better than the heatsink alone could.

To further help with reducing the amount of heat generated by a CPU, the voltage that a CPU runs at is now much lower than an older CPU. For example, most versions of the Intel i486 ran on 5V but the Intel Pentium 4 ran on 1.7V. The lower voltage means there is less current and heat is a product of voltage and current.

Another change over the years as CPUs have got more powerful is that newer CPUs contain multiple cores which can be thought of as a chip that contains multiple CPUs. This allows one core to carry out additional tasks while another core does something else. Software, however, has to be written to take advantage of these extra cores, such as the operating system which will divide up the tasks to give to each core. An example of a multi-core CPU in the photo above is the AMD Athlon 64 X2 CPU which contains two cores.

Before even CPUs came about with multi-cores, a big change that improved their performance was increasing the amount of data they could handle. The first CPUs were 4-bit meaning they could handle 4 bits of data, that is, 16 different values, which are transferred on the CPU's data bus. CPUs that came after were 8-bit and could deal with 256 different values. It should not be a surprise then that later CPUs were 16-bit, followed by 32-bit CPUs (such as the Intel i486) and more recently, 64-bit CPUs (for e.g., the AMD Athlon 64 X2 CPU).

Even with a CPU installed, without the PSU (Power Supply Unit) connected or working then nothing would happen if you tried to turn the computer on. Another very important part of a computer is the RAM (Random Access Memory), although the CPU has its own, tiny amount of internal RAM only a small amount of data can be stored there at one time so without the external RAM (external to the CPU) the computer wouldn't be able to do much.

A CPU must have insructions, the start up code, ready for it as soon as the power is turned on; these startup instructions are stored in the BIOS (Basic Input/Output System) which is stored in a ROM (Read Only Memory) chip. The BIOS of modern computers can be changed, such as to update it to provide new features or to fix bugs, however, this opens up the possibility of a corrupted BIOS which would stop the computer from starting.

The BIOS will check the system is running as it should and will display a limited amount of information about the hardware on screen, like how much RAM there is and if there are any errors. There will also be a setup configuration utility, usually accessed by pressing a certain button after power up, that allows the user to adjust settings such as the date and time, and what integrated devices should be enabled.

When the BIOS is checking the hardware it runs what is known as its POST (Power-On Self Test) and will test the RAM and look for connected peripherals, namely floppy drive, harddrive, CD-ROM and the like. As soon as it has done that and there aren't any serious problems, the BIOS will load the operating system (e.g., Windows) from the harddrive (or other device). The operating system can't be loaded first since, even if there were no need for tests, code either in ROM or RAM has to be available as startup code to load data from a peripheral like a harddrive.

Anyone who has had keyboard troubles or pressed a key on the keyboard when a computer starts up will be faced with the puzzling error message that reports a keyboard error and asks the user to press any key to continue despite the keyboard not working. The keyboard always has been for most computers the one input device you need more than any other but still that's no excuse for that stupid error message.

Microcomputers

Please go to Microcomputers.

BeagleBone Computers

Please go to BeagleBone Computers.

NVIDIA Jetson Nano

Please go to NVIDIA Jetson Nano.

The Asus Tinker Board

Please go to The Asus Tinker Board.

The Intel Galileo

Please go to The Intel Galileo.

The Raspberry Pi

Please go to The Raspberry Pi.

Create Your Own Computer

Please go to Create Your Own Computer

Repairs

Please go to Repairs

Tips and Tricks

Media Information Missing in Properties Window

Some programs, such as OBS, don't record useful information for a file such as its frame width and height, which should be accessible when you right-click the file in Windows' File Explorer and select Properties, then Details tab. You can, however, use a program to give you the information, and such a utility is Media info, downloadable from:

https://mediaarea.net/en/MediaInfo

After installing the program, right-click a media file and select Mediainfo; Mediainfo will launch with information about the video file. Alternatively, you could launch Mediainfo and then open a file (File->Open->File). For more detailed information about the file than what is shown in the default view select View->Tree.

Intel L1A4729 Memory Board

While computers of today have plenty of RAM, with values in the GB the norm, back in the earlier days of computers the size of the RAM was more in the MB. I had acquired this Intel memory expansion board (as seen below) and thought I would share it with you as it's a good example of how vastly technology has advanced since it was made.