2022/12/06

【My Study Note】Computer Hardware

Hardware Infotech

Contents

• Programs and Hardware
• Storage
• Power Supply

Programs and Hardware

Programs

Programs are basic instructions that tell the computer what to do.

EDB (External Data Bus)

EDB is a row of wires that interconnect the parts of our computer, kind of the veins in our body.

When transistors send a voltage to one of the wires, we say the state of the wire is on, or represented by a 1. If there’s no voltage, then we say that the state is off, represented by a 0. 

This is how we send around our ones and zeroes (how our bits physically travel around computer). 

The EDB comes in different sizes, 8 bit, 16 bit, 32, even 64. Can you imagine if you had 64 wires going? You can move around a lot more data. 

Registers

Inside the CPU there are components known as Registers. They let us store the data that our CPU works with. 

For example, if our CPU wanted to add two numbers, one number would be stored in “register a”. Another number would be stored in “register b”. The result of those two numbers would be stored in “register c”. 

Imagine the register is one of our chef’s work tables. Since she has a place to work, she can start to cook.

MCC (Memory Controller Chip)

The MCC is a bridge between the CPU and the RAM. 

This is how it works

The CPU talks to the MCC, and says, “hey, I need the instructions for step number three of this recipe”. The MCC finds the instructions for step number three in RAM, grabs the data, and sends it through the EDB.

Address Bus

The address bus connects the CPU to the MCC, and sends over the location of the data, but not the data itself. Then the MCC takes the address and looks for the data. And the date is then sent over the EDB.

Cache

Actually, RAM isn’t the fastest way we can get more data to our CPU for processing. The CPU also uses something known as Cache. Cache is smaller than RAM, but it let us store data that we use often, and let us quickly reference it. 

Think of RAM like a refrigerator full of food. It’s easy to get into, but it takes time to get something out. 
On the other side, Cache is like the stuff we have in our pockets. It’s used to store recently or frequently accessed data. 

There are three different cache levels in a CPU, L1, L2, and L3. L1 is the smallest and fastest cache. 

Clock Wire

Do you know how our CPU know when the set of instruction ends, and a new one begins? Our CPU has an internal clock that keeps its operations in sync. It connects to a special wire called clock wire. When you send or receive data, it sends a voltage to that clock wire to let the CPU know it can start doing calculations. 

Think of our clock wires as the ticking of a clock. For every tick, the CPU does one cycle of operations. Also, when you send a voltage to the clock wire, it’s referred to as a clock cycle.

Clock Speed

Have you ever seen a CPU in the store that has something labeled 3.4ghz? This number refers to the clock speed of the CPU. Which is the maximum number of clock cycles that it can handle in a set in a certain time period. 

3.40 gigahertz is 3.4 billion cycles per second. That’s super fast. But just because it can run at this speed, doesn’t mean it does. It just means that it can’t exceed this number.

Overclocking

There’s a way you can exceed the number of clock cycles on your CPU on almost any device. It’s referred to as overclocking and it increases the rate of your CPU clock cycles in order to perform more tasks. This is commonly used to increase performance in low-end CPUs.
» For more information about how to overclock your CPU

Storage

Data Size

Two basic hard drive types

• HDD (Hard Disk Drive)
• SDD (Solid State Drive)

HDD (Hard Disk Drive)

Source: Wikimedia Commons

HDDs use a spinning platter and a mechanical arm to read and write information. 

The speed that the platter rotate allows you to read and write data faster. This is commonly referred to as RPM (Revolution Per Minute). A hard drive with a higher RPM is faster, so if you go out and buy a hard drive today, you might see something like a 500 gigabyte with 5400 RPM.

HDDs are prone to a lot more damage because there are a lot of moving parts. But instead, it’s more affordable than SDD.

SDD

SDDs have no moving parts which mean it’s not gonna be easily damaged. The information is stored on microchips and data travels a lot faster than HDDs. The form factor for SSDs is also slimmer compared to their HDD cousins. But instead, it’s more expensive than HDDs.

Hybrid

Believe it or not, there are even hybrid SSD and HDD drives out there. They offer SSD performance where you need it. For things like system performance, such as booting your computer, along with hard disk drives for less important stuff, like basic file storage.

Interfaces that hard drives use to connect to our system

• ATA interfaces
• NVMe (NVM Express)

ATA interfaces

Source: Tech Station (SATA Pics)

The most popular ATA drive is a SATA (serial ATA) which uses one cable for data transfers. SATA drives are hot-swappable. It means you don’t have to turn off your machine to plug in a SATA drive. SATA drives move data faster and use a more efficient cable.

NVMe (NVM Express)

SATA has been the de facto interface for HDDs today. But people quickly found that using a SATA cable wasn’t good enough for some of the blazing-fast SSDs that were coming on the market. The interface couldn’t keep up with the speed of the newest SSDs. That is why another interface standard was created NVM Express.

Instead of using a cable to connect your drive to your machine, the drive was added as an expansion slot, which allows for greater throughput of data and increased efficiency.

Power Supply

Computers have a power supply that converts electricity from your wall to something usable. There are two types of electricity, DC (Direct Current) which flows in one direction, and AC (Alternating Current) which changes directions constantly. 

Our computers use DC voltage, so we have to have a way to convert the AC voltage from our power company to something we can use. That’s what our power supply does. It converts the AC we get from the wall into low-voltage DC power that we can use and transmit throughout our computers. 

Things most power supply has

• Fan
• Voltage information (normally listed underneath or on the side)
• Cables to power your motherboard
• Power cable

Voltage

We refer to the electricity pressure as voltage.

For example, if you plugged in that 120-volt appliance into a 220-volt outlet, the power would come busting through and fry your charger. If it was the other way around, and a 220-volt appliance was plugged into a 120-volt outlet, you wouldn’t have seen the same outcome. You’ll still be able to get electricity, but slowly.

However, in some cases, this can deteriorate the performance of the device and cause damage in the long term. So, as a general rule, be sure to use the proper voltage for your electronics.

Current (Amperage)

We refer to the amount of electricity coming out as current or amperage, and it’s measured in amps. 

We can think of amps as pulling electricity, as opposed to voltage, which pushes electricity. Amps will pull as much electricity as needed, but the voltage will just give you everything.

Look on the back of your device charges, you might see something like 1 or 2.1a. Charging a device with 2.1 amps will actually charge a device faster because it’s able to put current from a 2.1 amp than a 1 amp charger.

Wattage

Wattage is the amount of volts and amps that a device needs. 

If your power supply has too low of wattage, you won’t be able to power your computer, so make sure you have enough. This doesn’t mean that if you have a large power supply, you’ll overpower your computer. Power supplies just give you the amount that your system needs. 

You can power most basic desktops with a 500-watt power supply, but if you’re doing something more demanding on your computer, like playing a high-resolution video game or doing a lot of video production and rendering, you’ll likely need a bigger power supply for your computer. On the other hand, if all you’re doing is just browsing the Web, the power supply that comes with your computer should be fine.

Peripherals

Three most common USB (Universal Serial Bus)

Difference between MB and Mb/s

These are actually different units. MB is megabyte or unit of data storage, while Mb/s is a megabit per second, which is a unit of data transfer rate.

People often mistake speeds of 40 megabit per second to mean that you can transfer 40 megabytes of data per second. Remember, that one byte is 8 bits, so to transfer a one megabyte file in a second you need an 8 megabits per second connection speed. So, to transfer 40 megabytes of data in a second, you need a transfer speed of 320 megabits per second. You’ll also need comparable USB ports to go with your devices. 

USB ports

The ports are easy to differentiate. In general, USB 2.0 are black and USB 3.0 are blue and 3.1 ports are teal. (This may change depending on manufacturers)

Some common inputs standards

Hardware Infotech

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