PC Build Part 1: Purchase
This series is for a first-time builder. Please comment if you spot any errors or omissions or if something is inadequately explained — I’ll be happy to research the answer.
After watching me waste hours waiting for stuff to process on my laptop, my brother suggested investing in a desktop PC and, bright-eyed with his brand new CS degree, proposed we build it ourselves. The internet seemed to think this made sense.
The following is a report on our build. It is mostly meant to serve as a note-organizer and self-guide should I build again, but also to share with friends and family who helped, as well as spread valuable links I discovered with other new builders.
You want to value engineer your PC, i.e. maximize the PC’s function while minimizing costs to generate the highest functionality and value possible. The first question is: What is the PC’s function — video editing, music production, gaming, machine learning? You’ll want to research more, but here’s an overview of what to look for based on your intended function.
Note: The above video from Cybrary requires a login. I will refer to Cybrary’s free CompTIA videos several times in this series.
Start by familiarizing yourself with the parts.
Case aka chassis (pronounced chassy)
Cases will often be labeled ATX, MicroATX, and Mini-ITX, which refers to its compatibility with the various motherboard form factors (aka sizes). Make sure your case is big enough for your board.
Motherboard form factors: Size/Width/Height | Mini ITX/6.7"/6.7" | Micro ATX/9.6"/9.6" | ATX 9.6"/12" | E-ATX/13"/12".
The case is arguably the least important part you’ll buy — just make sure it has decent reviews and good ventilation to keep your components cool.
In the Cyber Monday frenzy, I bought the MasterBox Pro 5 RGB ATX Mid-Tower with 3 x 120mm RGB Fans, but probably would have thought twice had I seen what this YouTube reviewer said: “This is a good case to buy if you do not care about airflow and you care about looks and you just want something that’s cheap” … At least the LED lights are pretty? (So far temperatures are low and zero problems. But thought I’d share just as a PSA — obviously check user reviews.)
Motherboard (aka mainboard, sometimes called “mobo”)
The motherboard is the main circuit board in the computer. All motherboards do basically the same thing: provide slots for the CPU, memory, expansion cards, and a BIOS (more on BIOS later). A pattern of copper pathways covers the board for the electricity to travel between components which are soldered onto the circuit board. There are sockets and slots for removable/replaceable components. Replaceable components are called FRUs (Field Replaceable Units) and include the RAM, CPU, expansion cards (anything that fits in a PCIe slot), power supplies, and storage disks (hard drive, SSD). Some motherboards offer additional RAM slots or additional USB 3 ports. Others offer onboard graphics, onboard sound, additional hard drive controllers, etc. You probably neither need these, nor need to know what they are.
You do need to ensure compatibility with the CPU, which you might want to select first. (I bought mine together in a set.)
My motherboard is the ASUS Z370-A II. It is a “Z”-branded motherboard which means it has additional unlocked ability to control voltages and frequencies for the purpose of overclocking. More on overclocking in a later post.
CPU (Central Processing Unit)
The CPU is often called the “brain” of the computer. You can deep-dive into workings of the CPU, but be prepared to swim; my black-box understanding* is it takes instructions from the RAM, “processes” them (whatever that entails), and sends instructions to your other components to make your PC do everything it does.
*I provide a little more information in the overclocking section.
Some terms to know:
Speed (aka frequency)
This is the “clock speed” — how many ticks per second, which translates to how many operations go through the CPU per second. Modern CPUs perform billions-with-a-“b” operations per second! The latest CPUs have clock speeds as high as 4.30 GHz (> 4 billion operations per second) but you can still buy older models around 1.60GHz.
Modern CPUs have “multi-core processing”, i.e. they have more than one processing unit or core. 2 cores is called dual-core; 4 cores is called quad-core; 6 cores is called hex-core. Multiple cores enhance processing power. By distributing work amongst the processors, working in parallel across multiple cores (parallel processing), programs can execute functions faster and more efficiently. Before the technology was good enough (small enough in this case) to support multiple cores in one processor, you could actually install multiple CPUs on the motherboard, either by having one central processor with supporting processors which shared memory but were not connected to the operating system (asymmetric multiprocessing) or all the processors run tasks in the operating system (symmetric multiprocessing). Now, instead of having multiple processors, you can get the same effect by having multiple cores running tasks within one processor. And you can simulate having even more cores through multithreading.
Hyper-threading aka multi-threading
Hyper-threading virtually creates a second CPU. This does not mean processing power is doubled; it’s merely simulated. But, like having multiple cores, the distribution of the workload (parallel processing in virtual “cores”) allows for greater efficiency and is faster.
A good explanation: “It’s helpful to think of threads as “jobs”. A “core” represents an actual physical subset of a processor that can by itself handle processing, whereas a “thread” is how many actual processes the processor can handle at once.” (Source linked below.) More physical cores are better than more threads (since cores add actual computing capability, while threads merely subdivide the workload). But the more cores and threads, the better.
Threads can be prioritized and their assignments controlled by the operating system’s task scheduler. For example, for intensive applications (video editing, 3D modeling, compression, encryption, etc.) and multitasking, the threads may be assigned some work, then be interrupted by the task scheduler to move onto a different job, do some work on that job, and so on and so forth, until the job is completed. If there are a lot of applications running, each core will do some work, subdividing the labor between its threads.
Cache size / type
Cache is basically the CPU’s short-term memory. Before making a request to the RAM, the CPU checks to see if the operation has already been performed. If it has, it simply reloads the result from the previous calculation without having to compute it again. This makes it the fastest memory base but also the most limited, since the cache is quite small compared to the RAM and hard disks.
Like most current CPUs, my Intel i7 is a 64-bit processor. The earliest CPU’s were 8-bit processors, meaning they could process 8 binary digits (bits) at a time (like 00101001).
A bit of history: Operating systems and applications lagged behind hardware. In order to use the full functionality of a 64-bit processor, you need a 64-bit operating system to deliver 64 bits at a time. If you installed a 32-bit operating system with a 64-bit processor, it would switch the processor down to 32-bit mode. That’s a bit like buying a sportscar (64-bit processor) but driving it at 30 mph (32-bit OS). Even when 64-bit operating systems were released, applications that were 32 bit had to be translated in real time to 64-bit which added processing time. As a result, adoption of 64 bit operating systems was slow.
A note on names: A 64-bit CPU is designated x64. The 32-bit CPU is designated x86, not x32. (The name x86 is not related to the amount of bits of addressable memory.)
My CPU has six physical cores (aka hex-core) and twelve threads.
Heat sink aka cooler
Remember how we said the CPU performs billions of operations per second? All that work creates heat. The CPU can run at temperatures over 200 degrees Fahrenheit, but if it gets too hot it can be damaged and destroy other components. Enter the heat sink.
The heat sink sits atop the CPU. A thin layer of “thermal paste” aka thermal cooler acts as a heat conductor between the heat-spreader of the CPU and the baseplate of the cooler, facilitating heat absorption and dissipation.
This can be a fan or a liquid cooling system. I installed a fan, but in retrospect the liquid cooling system seems to be better and isn’t much more expensive.
RAM (random access memory) short-term memory
RAM is the PC’s main working memory and is measured by the amount of information it can hold (in gigabytes) and the speed at which it communicates with the CPU (in megahertz).
Unlike the hard drives, RAM requires power to retain information. When the computer is powered off, the RAM is emptied.
I got 16GB of RAM which is probably more than I need, but it’s a high-value component for its price. More RAM access means you can work with larger documents and run more programs (or, if you’re like me, keep every browser tab you’ve ever opened open). Additional RAM improves system performance, processing speed, and overall stability.
When purchasing RAM sticks, make sure the RAM matches your CPU and motherboard. Each RAM stick has keyed pins that fit corresponding keyed DIMM slots. You won’t be able to install it if these don’t match. 32-bit CPUs are limited to just 4 gb of RAM. 64-bit CPUs can access 16gb or more of RAM.
The RAM has to be as fast as the motherboard specification. If adding additional RAM, make sure to match the existing RAM’s speeds. If you don’t match the speeds, all the RAM will go at the speed of the slowest RAM you install.
“Memory” most often refers to RAM, but there are other kinds of memory. The CPU contains SRAM (static random access memory) which is used for the “cache memory” and the register file (discussed above), and is a much faster than DRAM. And of course there are the hard drives.
Something to learn more about at some point: “RAM is basically just a large number of capacitors bound together. Each one holds one bit, whose value depends on the charge of the capacitor, 1 if high voltage and 0 if low.”
HDD (hard disk drive) aka mechanical hard drive
The hard disk drive (HDD) aka mechanical hard drive uses magnetism and a mechanical arm with a read/write head (think of a record player) to move around and read information from the right location on a storage platter, which is sort of like an extra-compact compact disk. The faster the platter spins, the faster an HDD can perform. Typical laptop drives today spin at either 5400 RPM (revolutions per minute) or 7200RPM. Mine is the 5400 RPM Class.
The hard disk is a non-volatile storage medium meaning, unlike RAM, it “remembers” information when the computer is powered off.
SSD (solid state drive)
The solid state drive (SDD) can be thought of as an oversized and more sophisticated version of a USB memory stick. Like a memory stick, there are no moving parts to an SSD. Rather, information is stored in microchips.
SSDs have good read-longevity. Data stored on a SSD will be maintained for over 200 years.
GPU (graphics processing unit) aka graphics card aka video card
Some CPUs and motherboards come with integrated GPUs so if you don’t have high-level GPU requirements, you might not need one at all.
I don’t game so I thought the GPU wouldn’t be that important. It turns out that machine learning relies heavily on the GPU, and it’s important to get NVIDIA. Another endorsement for researching based on your intended function.
PSU (power supply unit)
Check your power supply needs with this calculator and then level up.
According to my power supply calculation, I could get away with a 500 Watt PSU, but I got a 1000 Watt. A better PSU will not make the computer run faster, improve graphics, make the processor stronger, increase the amount or speed of the RAM, increase storage space, or increase the rotational speed of the hard drive’s platters. But a powerful PSU not only can save long-term electricity costs, it can extend the life of components by keeping the machine cool. (Heat builds up within a power supply when it is being used, and straining a supply causes excessive heat — an electronic component’s enemy — to build up in its components.)
Historically, display devices were CRT (Cathode Ray Tubes) monitors. These were similar to cathode ray TVs — they were big and bulky and generated a lot of heat. In CRT monitors, the screen was made up of red, green, and blue (RGB) dots. There were three separate electron-guns, one for each color. CRT monitors suffered from “burn in” — when a static image was left on the screen, the image would actually burn itself into the screen. That’s why screen savers were invented, to put moving images on the screen so no single image would burn to the screen.
Today, the most common display device is the flat panel LCD (Liquid Crystal Display). In LCD screens, liquid crystals change their light-blocking properties based on electrical signals applied to them. The LCD does not itself emit light, so LCD panels have LEDs (Light Emitting Diodes) behind them.
The fact that the liquid crystals can change their light blocking properties based on electrical signals seems to have all sorts of futuristic applications. For example, check out the Samsung Smart Window LCD.
Other displays include OLEDs (organic light-emitting diodes) and QLEDs (quantum-dot light-emitting diodes) and they are interesting to read about. Basically, you’ll get lower power consumption, deeper black, better contrast, and even curved and flexible screens with these newer and more expensive displays.
But this is all way TMI. All you really need is a decently-reviewed monitor that matches the quality of your graphics card. (Little sense in getting an amazing graphics card if the monitor’s refresh frequency is slow, and vice-versa.)
Mine is the Acer R240HY bidx 23.8-Inch IPS HDMI DVI VGA (1920 x 1080) Widescreen Monitor and I got two. It has a resolution of 1920 x 1080, which is Full HD. My refresh frequency is 60 Hz which is probably not good enough for my kickass GPU, but sufficient for my purposes since I’m not a gamer. The response time is 4 ms GTG (grey to grey). That means it takes 4 milliseconds for a pixel to go from one state to another; that’s 250 color-states per second. Something that amazed me: it has 16.7 million supported colors!
A wireless internet card plugs into one of the PCIe expansion slots on the motherboard. It has antennae which stick out the back side of the case and transmit and receive radio waves (which it then translates into machine code, and vice-versa).
You don’t have to install a card to the motherboard. If you will only be using an ethernet connection, you don’t need one at all. If you ever do need one, you can grab a USB wifi adapter from any electronics store. A USB adapter will not give you the speeds of the PCI wireless adapter card, but it’s a cheaper option if you don’t plan to use wifi often.
Mouse and keyboard
You need a USB-connected keyboard to start. You can change over to a bluetooth keyboard later, but you can’t use it to set up. Other than that, get whatever keyboard and mouse (or other pointing device: trackpad, trackball, stylus, or joystick) you want.
I ended up needing an extra HDMI, DisplayPort-to-HDMI, and a fan extension cable. You may or may not need extra cables.
Cables are not the most interesting part of a PC, but having a basic understanding of all the different kinds of cables makes them a bit less bewildering.
An OS can also be command-line only. The original UNIX and DOS did not have GUIs so, rather than pointing and clicking, you had to know and type all the commands. (Beats having to “speak machine”.) You can open your terminal or command prompt to test it out.
You’ll want to have the OS loaded onto a flash drive. If you’re buying Windows 10, you can purchase this from Microsoft. If you’re downloading a Linux system like Ubuntu, use another computer to load it onto a flash drive. You can have both (or as many as you want) with dual-booting or a virtual system. I will probably download Ubuntu at some point since many ML programs are Linux-based.
Dual boot instructions (see comments)
Antistatic wrist strap, phillips head screwdriver (magnetic tip preferable), zipties, velcro ties, wire cutters, sticky notes, pen, ziplock bags, flashlight
There is a handy site called pcpartpicker which will check components for compatibility as well as cross-check prices. It’s important to note that parts may be technically compatible, but not well-suited to eachother. You want to avoid combinations that create bottlenecks on your highest-grade hardware.
Here are my components. (We shopped Black Friday and Cyber Monday for the sick dills.)
If prices are competitive, it’s a good idea to get what you can locally. There are the feel-goods of supporting the local economy, sure, but also you can get valuable information from the techs at your local computer shop. If you’ve never built before, there’s a lot you can pick up talking face to face. Also, if you’re just looking to get an awesome PC at below-retail price but don’t want to build it yourself, they might build it for you. At my local store, you can just buy all the parts and they’ll build it for you for a flat $250 with a three-year warranty.
Continue to PC Build Part 2: Prepare