{ "version": "1.0.0", "segments": [ { "speaker": "Josh", "startTime": "0.765", "endTime": "4.677", "body": "I had my first experience with computer hardware when I was 8 years old." }, { "speaker": "Josh", "startTime": "5.655", "endTime": "9.248", "body": "My dad had brought home an old computer from work that wasn't being used anymore." }, { "speaker": "Josh", "startTime": "10.609", "endTime": "16.179", "body": "We took it apart, dove inside the case, made sure to avoid touching any capacitors, and" }, { "speaker": "Josh", "startTime": "16.179", "endTime": "17.051", "body": "just looked around." }, { "speaker": "Josh", "startTime": "18.603", "endTime": "20.495", "body": "We took out the floppy drive, the motherboard," }, { "speaker": "Josh", "startTime": "19.73", "endTime": "24.514", "body": "sticks of RAM, and the hard drive. We even took the case of the hard drive apart" }, { "speaker": "Josh", "startTime": "24.514", "endTime": "31.021", "body": "so we could look at the shiny platters inside. To this day, that's probably one of my favorite" }, { "speaker": "Josh", "startTime": "31.021", "endTime": "36.326", "body": "pieces of computer hardware. There's something mesmerizing about those perfectly reflective" }, { "speaker": "Josh", "startTime": "36.326", "endTime": "42.852", "body": "platters. And the second you touch them, your fingerprints are all over them. Fun fact, there" }, { "speaker": "Josh", "startTime": "42.852", "endTime": "48.157", "body": "are some powerful rare earth magnets in there that you can take out and repurpose. Just be careful" }, { "speaker": "Josh", "startTime": "48.157", "endTime": "53.563", "body": "you don't pinch your fingers between them. So that was the first time I ever took apart a computer," }, { "speaker": "Josh", "startTime": "53.903", "endTime": "60.73", "body": "but building one, that happened in college. It was my second year, and I wanted a server to run" }, { "speaker": "Josh", "startTime": "60.73", "endTime": "67.416", "body": "virtual machines on from my dorm room. My college had a slash 16 network, which means every network" }, { "speaker": "Josh", "startTime": "67.416", "endTime": "73.442", "body": "jack you plugged into had a public IP. You could plug in a computer, and boom, it was accessible" }, { "speaker": "Josh", "startTime": "73.442", "endTime": "79.848", "body": "on the internet. So I specced it out and placed my Newegg order. This was before Newegg was acquired" }, { "speaker": "Josh", "startTime": "79.848", "endTime": "86.114", "body": "by a Chinese company. Then for the next few weeks, as parts came in, I would hike up the hill to the" }, { "speaker": "Josh", "startTime": "86.114", "endTime": "92.741", "body": "mail room, pick up each package, and make the one mile walk back to my dorm room. A mile in both" }, { "speaker": "Josh", "startTime": "92.741", "endTime": "98.366", "body": "directions with each individual component really makes you understand just how many different parts" }, { "speaker": "Josh", "startTime": "98.366", "endTime": "104.412", "body": "you need for a computer. Once all the parts came in, I got it assembled and up and running." }, { "speaker": "Josh", "startTime": "105.413", "endTime": "111.299", "body": "So in this season, I want to cover each main component of a computer. We all use them every" }, { "speaker": "Josh", "startTime": "111.299", "endTime": "116.964", "body": "day, but do we really understand them? The component that does everything you ask it," }, { "speaker": "Josh", "startTime": "116.964", "endTime": "123.651", "body": "on this episode of In The Shell. The wrong thing to do is just go out and buy a computer" }, { "speaker": "Josh", "startTime": "123.651", "endTime": "128.576", "body": "and then learn about it. You'll learn, but you'll learn a lot of things that maybe you didn't want" }, { "speaker": "Josh", "startTime": "128.576", "endTime": "135.282", "body": "to learn. A computer that you buy today will likely be obsolete six months from now, and there's not a" }, { "speaker": "Josh", "startTime": "135.282", "endTime": "142.589", "body": "dang thing that you can do about it. My name is Josh, and I'm able to keep this podcast independent" }, { "speaker": "Josh", "startTime": "142.589", "endTime": "148.595", "body": "and advertisement-free because of support from listeners like you. If you are finding value in" }, { "speaker": "Josh", "startTime": "148.595", "endTime": "155.502", "body": "what I'm doing here, consider becoming a paid supporter at members.sideofburritos.com. And as" }, { "speaker": "Josh", "startTime": "155.502", "endTime": "161.548", "body": "a thank you, members get early access to new videos, ad-free versions of everything, bonus content," }, { "speaker": "Josh", "startTime": "161.788", "endTime": "167.534", "body": "and access to a live monthly Q&A. Thanks for considering. Now let's get back to the show." }, { "speaker": "Josh", "startTime": "168.535", "endTime": "176.602", "body": "At its core, pun intended, the CPU is a processor. It processes instructions. When your computer runs" }, { "speaker": "Josh", "startTime": "176.602", "endTime": "183.609", "body": "a program, or even just boots up, the CPU fetches instructions from memory, decodes them, and executes" }, { "speaker": "Josh", "startTime": "183.609", "endTime": "191.016", "body": "them one after another at lightning speed. This cycle of fetch, decode, execute repeats billions of" }, { "speaker": "Josh", "startTime": "191.016", "endTime": "198.223", "body": "times per second, synchronized by the CPU's internal clock. It also has a small set of specialized tools" }, { "speaker": "Josh", "startTime": "198.223", "endTime": "206.511", "body": "to help get its job done. One tool is the Arithmetic Logic Unit, ALU, which handles basic math and logical" }, { "speaker": "Josh", "startTime": "206.511", "endTime": "213.698", "body": "comparisons. Another is the Control Unit, which manages the flow of data, telling memory and input" }, { "speaker": "Josh", "startTime": "213.698", "endTime": "220.946", "body": "and output devices where to send or receive information. The CPU also uses tiny storage areas" }, { "speaker": "Josh", "startTime": "220.946", "endTime": "228.853", "body": "called registers to keep data it's actively working on. Modern CPUs often include multiple processing" }, { "speaker": "Josh", "startTime": "228.853", "endTime": "237.161", "body": "units called cores on one chip. A quad-core CPU has four cores that can work on tasks in parallel," }, { "speaker": "Josh", "startTime": "237.422", "endTime": "243.407", "body": "allowing the CPU to handle multiple tasks at the same time more efficiently. Despite all these" }, { "speaker": "Josh", "startTime": "243.407", "endTime": "249.754", "body": "advancements, the CPU's fundamental job remains the same, to execute instructions and process data." }, { "speaker": "Josh", "startTime": "250.935", "endTime": "256.52", "body": "But how does this tiny chip actually switch and calculate so incredibly fast? The transistor." }, { "speaker": "Josh", "startTime": "257.201", "endTime": "262.166", "body": "A transistor is essentially a microscopic electrical switch. It can turn" }, { "speaker": "Josh", "startTime": "262.166", "endTime": "268.198", "body": "on or off to either allow electrical current to flow or to block it. This on-off behavior" }, { "speaker": "Josh", "startTime": "268.198", "endTime": "274.371", "body": "is exactly what we need to represent the ones and zeros of binary code, the language of computers." }, { "speaker": "Josh", "startTime": "275.239", "endTime": "280.202", "body": "Each transistor can be in an on state, allowing current representing a one," }, { "speaker": "Josh", "startTime": "280.403", "endTime": "286.94", "body": "or an off state, blocking current representing a zero. By arranging billions of transistors" }, { "speaker": "Josh", "startTime": "286.94", "endTime": "293.88", "body": "into complex circuits, engineers create logic gates and high-level components that perform all" }, { "speaker": "Josh", "startTime": "293.88", "endTime": "301.587", "body": "the calculations and decision making inside the CPU. For example, combinations of transistors form" }, { "speaker": "Josh", "startTime": "301.587", "endTime": "307.942", "body": "logic gates like AND, OR, and NOT, which in turn combine to implement everything from addition" }, { "speaker": "Josh", "startTime": "307.942", "endTime": "314.317", "body": "and subtraction to multimedia processing. It's incredible to realize that even the most advanced" }, { "speaker": "Josh", "startTime": "314.317", "endTime": "314.64", "body": "computation," }, { "speaker": "Josh", "startTime": "314.64", "endTime": "321.808", "body": "ultimately boil down to transistors switching on and off. Historically, transistors replaced" }, { "speaker": "Josh", "startTime": "321.808", "endTime": "329.359", "body": "their larger predecessors, vacuum tubes, in the 1950s and 60s. Early computers like the 1940s" }, { "speaker": "Josh", "startTime": "329.359", "endTime": "336.769", "body": "ENIAC used around 18,000 vacuum tubes as switches, and those tubes ran hot and burnt out frequently." }, { "speaker": "Josh", "startTime": "337.756", "endTime": "344.924", "body": "Transistors were first demonstrated in 1947 at Bell Labs. They were tiny, used far less power," }, { "speaker": "Josh", "startTime": "345.367", "endTime": "352.113", "body": "ran cooler, and were more reliable. Over the next decade, engineers dramatically improved" }, { "speaker": "Josh", "startTime": "352.113", "endTime": "358.939", "body": "transistor designs. By the mid-1960s, a new manufacturing approach, the planar process," }, { "speaker": "Josh", "startTime": "359.241", "endTime": "365.463", "body": "made it possible to build many transistors on a single slice of silicon. This led to the first" }, { "speaker": "Josh", "startTime": "365.463", "endTime": "367.114", "body": "integrated circuits and eventually..." }, { "speaker": "Josh", "startTime": "367.114", "endTime": "375.961", "body": "the first microprocessors in the early 1970s. For perspective, Intel's first CPU, the 4004" }, { "speaker": "Josh", "startTime": "375.961", "endTime": "383.996", "body": "in 1971, had about 2,300 transistors, compared to modern CPUs that can house tens of billions" }, { "speaker": "Josh", "startTime": "383.996", "endTime": "391.525", "body": "of transistors on one chip. This rapid growth in transistor counts followed a trend known as" }, { "speaker": "Josh", "startTime": "391.525", "endTime": "397.308", "body": "Moore's Law, the observation that roughly every two years, the number of transistors on a chip" }, { "speaker": "Josh", "startTime": "397.308", "endTime": "404.836", "body": "doubles, which I talked about more in Season 2, Episode 2 on Gordon Moore. When you hear that a" }, { "speaker": "Josh", "startTime": "404.836", "endTime": "411.816", "body": "CPU runs at 3GHz, what that actually means is that its internal clock ticks 3 billion times per second." }, { "speaker": "Josh", "startTime": "412.405", "endTime": "419.588", "body": "Each tick is an opportunity for the CPU to move one tiny step forward in the fetch-decode-execute cycle." }, { "speaker": "Josh", "startTime": "419.588", "endTime": "423.294", "body": "One other important aspect of CPUs is their architecture." }, { "speaker": "Josh", "startTime": "423.999", "endTime": "435.642", "body": "CPU architecture means the basic set of machine instructions a CPU understands to carry out fundamental operations, things like arithmetic, logic, and moving data around." }, { "speaker": "Josh", "startTime": "436.368", "endTime": "441.041", "body": "Over the years, different families of CPUs have developed their own languages." }, { "speaker": "Josh", "startTime": "441.041", "endTime": "451.939", "body": "The most common architectures you'll hear about today are x86, x86-64, which is x86's 64-bit extension, and ARM." }, { "speaker": "Josh", "startTime": "452.946", "endTime": "464.387", "body": "Modern Intel and AMD desktop CPUs use the x86-64 architecture, which is basically a 64-bit evolution of the older 32-bit x86 standard." }, { "speaker": "Josh", "startTime": "464.387", "endTime": "472.062", "body": "The jump to x86-64 around the early 2000s was a big deal because it expanded the CPU's capability." }, { "speaker": "Josh", "startTime": "472.876", "endTime": "482.394", "body": "Older 32-bit x86 chips could only directly use about 4GB of RAM, whereas 64-bit CPUs can address" }, { "speaker": "Josh", "startTime": "482.394", "endTime": "490.347", "body": "vastly more memory, theoretically up to 16 exabytes. Another reason CPU architecture is a big deal" }, { "speaker": "Josh", "startTime": "490.347", "endTime": "497.974", "body": "is the difference in performance and efficiency. x86 and x86-64 chips, the kind in most desktops" }, { "speaker": "Josh", "startTime": "497.974", "endTime": "506.272", "body": "and laptops. They have complex instruction sets, often called CISC, spelled C-I-S-C, which include" }, { "speaker": "Josh", "startTime": "506.272", "endTime": "513.248", "body": "many built-in operations. These CPUs tend to be very powerful and capable of handling heavy workloads" }, { "speaker": "Josh", "startTime": "513.248", "endTime": "519.126", "body": "like video editing, gaming, and software development, but they also use more electricity" }, { "speaker": "Josh", "startTime": "519.126", "endTime": "525.289", "body": "and run hotter as a trade-off. On the other hand, ARM CPUs use a reduced" }, { "speaker": "Josh", "startTime": "524.536", "endTime": "530.606", "body": "instruction set called RISC, spelled R-I-S-C, which is focused on efficiency." }, { "speaker": "Josh", "startTime": "525.289", "endTime": "525.309", "body": "." }, { "speaker": "Josh", "startTime": "525.309", "endTime": "525.329", "body": "." }, { "speaker": "Josh", "startTime": "525.329", "endTime": "525.35", "body": "." }, { "speaker": "Josh", "startTime": "531.514", "endTime": "536.717", "body": "ARM chips are designed to do more with less. They draw far less power and run cooler," }, { "speaker": "Josh", "startTime": "536.939", "endTime": "541.839", "body": "which is why they dominate in smartphones, tablets, and other battery-powered devices" }, { "speaker": "Josh", "startTime": "541.839", "endTime": "548.373", "body": "where energy efficiency is crucial. An ARM-based phone can run all day on a small battery." }, { "speaker": "Josh", "startTime": "549.402", "endTime": "555.432", "body": "Historically, the trade-off was that ARM's CPUs weren't as powerful as their x86 counterparts." }, { "speaker": "Josh", "startTime": "555.775", "endTime": "560.978", "body": "They handled everyday tasks just fine, but weren't geared for the really demanding stuff." }, { "speaker": "Josh", "startTime": "561.784", "endTime": "568.46", "body": "However, that line is blurring today. A great example is Apple's M1 chip and its successors" }, { "speaker": "Josh", "startTime": "568.46", "endTime": "575.478", "body": "used in newer Macs. It's an ARM-based CPU that proved ARM chips can be both extremely powerful" }, { "speaker": "Josh", "startTime": "575.478", "endTime": "577.01", "body": "and power-efficient." }, { "speaker": "Josh", "startTime": "577.01", "endTime": "586.072", "body": "In some cases, Apple's ARM CPUs are on par with or even outperformed traditional PC x86 chips while still running cool." }, { "speaker": "Josh", "startTime": "593.176", "endTime": "597.697", "body": "And look at how the CPU actually fits into a PC when you are building one." }, { "speaker": "Josh", "startTime": "598.646", "endTime": "603.913", "body": "Physically, a CPU is a small squarish chip that needs to be installed onto the motherboard." }, { "speaker": "Josh", "startTime": "603.913", "endTime": "608.152", "body": "The motherboard is something we'll be covering in detail in a future episode." }, { "speaker": "Josh", "startTime": "608.757", "endTime": "616.366", "body": "The motherboard has a special CPU socket, a slot that is designed to hold the CPU, and connect it to the rest of the system." }, { "speaker": "Josh", "startTime": "616.931", "endTime": "625.408", "body": "Every motherboard model supports only a particular type of socket, and a CPU will only work if it matches that socket on the motherboard." }, { "speaker": "Josh", "startTime": "626.134", "endTime": "629.484", "body": "This is why, if you pick an AMD Ryzen CPU," }, { "speaker": "Josh", "startTime": "629.484", "endTime": "632.909", "body": "You need a motherboard with the correct AMD socket for that chip." }, { "speaker": "Josh", "startTime": "633.73", "endTime": "638.858", "body": "Once the CPU is seated in the motherboard, the next crucial step is keeping it cool." }, { "speaker": "Josh", "startTime": "639.398", "endTime": "642.843", "body": "As powerful as these chips are, they generate a lot of heat." }, { "speaker": "Josh", "startTime": "643.624", "endTime": "650.714", "body": "Without proper cooling, a CPU would overheat and shut down, or throttle itself dramatically to avoid damage." }, { "speaker": "Josh", "startTime": "651.355", "endTime": "657.905", "body": "So in your PC build, after the CPU is in the socket, you'll attach a CPU cooler on top of it." }, { "speaker": "Josh", "startTime": "657.905", "endTime": "668.419", "body": "This might be an air cooler, a metal heatsink with a fan, or a liquid cooler, but either way it serves the same purpose, to carry heat away from the CPU." }, { "speaker": "Josh", "startTime": "669.761", "endTime": "672.706", "body": "Thermal paste is applied between the CPU and the cooler." }, { "speaker": "Josh", "startTime": "673.186", "endTime": "681.959", "body": "It's a tiny dab of gray stuff that ensures there are no air gaps and maximizes heat transfer between the CPU's surface and the cooler's surface." }, { "speaker": "Josh", "startTime": "681.959", "endTime": "688.918", "body": "base. When done correctly, this cooling setup keeps the CPU at a happy operating temperature" }, { "speaker": "Josh", "startTime": "688.918", "endTime": "695.205", "body": "even under load. As I was going through my script for this episode, there was one question I kept" }, { "speaker": "Josh", "startTime": "695.205", "endTime": "701.042", "body": "asking myself that I really wanted to know, and that's why are these tiny transistors made of" }, { "speaker": "Josh", "startTime": "701.042", "endTime": "708.043", "body": "silicon? Silicon is one of the most abundant elements on earth. Common sand is largely silicon" }, { "speaker": "Josh", "startTime": "708.043", "endTime": "714.757", "body": "dioxide, which means it's cheap and widely available. But more importantly, silicon is a" }, { "speaker": "Josh", "startTime": "714.757", "endTime": "721.003", "body": "semiconductor, meaning it can act as an electrical conductor or an insulator under different conditions." }, { "speaker": "Josh", "startTime": "721.615", "endTime": "729.085", "body": "In pure form, silicon doesn't conduct electricity well. However, by doping it, introducing tiny" }, { "speaker": "Josh", "startTime": "729.085", "endTime": "734.433", "body": "amounts of other elements, like phosphorus or boron, we can tweak its electrical properties." }, { "speaker": "Josh", "startTime": "734.433", "endTime": "743.624", "body": "Doped silicon can carry current in a controlled way, creating regions that either have excess electrons, N-type, or excess holes, P-type." }, { "speaker": "Josh", "startTime": "744.258", "endTime": "750.712", "body": "Put an N-type or P-type silicon together, and you get a transistor that can switch on or off at your command." }, { "speaker": "Josh", "startTime": "751.876", "endTime": "754.614", "body": "Additionally, silicon is friendly to manufacturing." }, { "speaker": "Josh", "startTime": "755.042", "endTime": "763.989", "body": "It can be refined into extremely pure, single crystals, and then sliced into thin wafers you might have seen in photos of chip factories." }, { "speaker": "Josh", "startTime": "765.072", "endTime": "772.65", "body": "Those wafers are the platform on which billions of transistors are fabricated, using processes like photolithography." }, { "speaker": "Josh", "startTime": "773.283", "endTime": "779.431", "body": "The abundance of silicon means we can produce these wafers in huge quantities relatively cheaply." }, { "speaker": "Josh", "startTime": "779.839", "endTime": "786.907", "body": "And the material stability and reliability mean the resulting chips can run for years without degrading." }, { "speaker": "Josh", "startTime": "786.907", "endTime": "790.074", "body": "It really is amazing when you stop to think about it." }, { "speaker": "Josh", "startTime": "790.708", "endTime": "796.736", "body": "A CPU is this small piece of material that sits quietly inside your computer, yet it does so much." }, { "speaker": "Josh", "startTime": "797.512", "endTime": "801.067", "body": "That old machine I took apart with my dad felt so powerful," }, { "speaker": "Josh", "startTime": "801.497", "endTime": "807.463", "body": "yet today's CPUs run thousands of times faster and pack far more complexity." }, { "speaker": "Josh", "startTime": "810.406", "endTime": "813.675", "body": "In the Shell is written, researched, and recorded by me," }, { "speaker": "Josh", "startTime": "814.37", "endTime": "816.291", "body": "the ARM-based podcaster," }, { "speaker": "Josh", "startTime": "817.619", "endTime": "820.091", "body": "if you are listening in an app that lets you rate shows," }, { "speaker": "Josh", "startTime": "820.398", "endTime": "822.441", "body": "please take a minute to rate this one." }, { "speaker": "Josh", "startTime": "823.075", "endTime": "824.832", "body": "I would truly appreciate it." }, { "speaker": "Josh", "startTime": "826.814", "endTime": "831.657", "body": "I always heard that if you're hiking in the woods, bring a piece of fiber optic cable with you." }, { "speaker": "Josh", "startTime": "833.006", "endTime": "835.437", "body": "If you get lost, you can bury it," }, { "speaker": "Josh", "startTime": "835.621", "endTime": "839.381", "body": "and 15 minutes later, five backhoes will be there to dig it up." }, { "speaker": "Josh", "startTime": "841.264", "endTime": "848.747", "body": "That's it. Take care, and I'll see you next time." } ] }