When looking for a new computer, choosing among the various options can be overwhelming. Should you get the new $1,300 MacBook or perhaps try a $90 Symple PC? And what do all the specs about “2.5GHz processors,” “RAM” and “SSD” even mean? To answer these questions, we dissect the functionality and cost of a $1,100 13’’ MacBook Pro. All of these prices are approximate, and are only meant to reflect the relative costs of the parts of a laptop, so while this will not decide for you what laptop to buy, hopefully it will make the process of choosing a little bit easier.

The Motherboard

(MacBook Pro 13’’ motherboard: ~$250)

Motherboards
The motherboard is a computer’s main component. It has ports to hold many of the most important electric components of a computer, such as the central processor (see below), memory, USB, and others. As such, it is often one of the most expensive parts of a computer, especially in laptops: it requires a lot of effort to design the motherboard in a way that fits all of the components in a compact space.

Processor

(2.5GHz dual-core Intel Core i5: ~$250)

Intel_core_i5

When people talk about how “powerful” a computer is, they are often referring to its processor. The processor is the part of a computer that actually runs the computer’s instructions. When looking at a processor, there are two important numbers that tell you how “powerful” it is. The first is how many cores the processor has. Each core in a processor can essentially be viewed as a miniprocessor that runs a computer’s instructions. Having multiple cores is especially helpful when a computer performs large computations. For example, if a computer with two cores is adding 1,000,000 numbers, it could halve the amount of time it takes to add these numbers by adding 500,000 numbers in one core and 500,000 in the other, instead of adding all 1,000,000 in just one core. The second important number is the processor’s speed, or how many instructions each core in the processor can run per second. This number is usually given in Hertz, so each core in a 2.5GHz (GigaHertz) processor can run 2,500,000,000 instructions per second!

RAM

(4GB 1600MHz DDR3 SDRAM: ~$50)

RAM

RAM, or random-access memory, is a special type of memory that has very fast reading and writing times. One of the biggest processes that slows down a computer is writing to and reading from memory (e.g. the delay you have in Microsoft Word when saving your document). Since all programs require some memory to function, all modern computers contain RAM. Its fast reading and writing times allow programs to temporarily store information without causing a large time delay. Usually, the more RAM your computer has, the more programs it can run at once without significant lag time. Unfortunately, RAM is also relatively expensive compared to standard disk memory.

Hard Drive

(500GB Serial ATA Drive @ 5400 rpm: ~$50)

HardDrive

The hard drive of a computer is the part that stores all of your information. Everything that you have ever “saved” or “stored” on your computer is contained here. There are currently two main types of hard drives: HDD and SSD. An HDD, or hard disk drive, contains metal disk-like platters that store all of your data. Information is read from and written to the platters by a small “head” contained within the hard drive (imagine a record-player head on a disk, except much smaller). However, because of the moving parts required in an HDD, there is a limitation in terms of how quickly certain parts of a disk can be accessed and how small an HDD can be. On the other hand, SSDs, or solid-state disks, store memory on interconnected memory chips. This allows SSDs to be both smaller and faster than HDDs, but makes them about twice as expensive as well. Currently, SSDs are mostly used for ultrabooks whereas desktops and laptops still use the standard HDD.

Video/Graphics card

(Intel HD Graphics 4000*: $0) *included with processor

GraphicsCard

A graphics card is a special component that controls how graphics are displayed on the screen. It often has a separate processor, the graphics processing unit (GPU), just for this purpose. For the gamers out there, this card is the one that has the biggest impact on how many frames per second (fps) your machine can run. For many laptops, a basic graphics card is included with the processor, but for people who want a better gaming or video experience, video and graphics cards can range from $50 to well over $5,000.

Monitor

(13’’ LED screen: ~$100)

Screen

No matter how good a graphics card you have, it is pointless if your monitor cannot display those graphics in their full glory. Companies often brag about the screen resolution on their latest and newest laptops. The screen resolution is usually given as two numbers in the form a x b, where a is the number of pixels that span the length of the screen and b is the number of pixels spanning the height of the screen. A 1600 x 900 screen resolution is thus 1600 pixels across and 900 pixels high. On a computer, the more pixels there are, the better the images will look. However, the bigger a screen is and the more pixels a screen has, the more expensive the it will be.

Other (~$400)

In addition to the components mentioned above, there are also many other factors that play into the cost of a computer. Computers have additional components such as the battery, speaker and camera, and if you want extra features such as a touchscreen or a backlit keyboard, those will add to the cost. Furthermore, the manufacturing and design of the computer will play into the final price you pay.

Final Notes

While features such as a backlit keyboard and built-in camera can be really nifty, the main factors that affect the cost of a computer lie beneath the metal frame — the motherboard and processor. Also, every computer is different, so if you’re buying a gaming laptop, you’ll be paying a lot more for the RAM and graphics card than those on a MacBook Pro. However, now a computer’s specs won’t just be an intimidating table of numbers, and you’ll know the difference you’re paying for when deciding between a computer with a dual-core 2.5GHz processor and one with a single-core 2.8GHz processor.

About The Author

Eugene Tang

Eugene Tang is currently a Junior studying computer science at Princeton University. He loves science, but unfortunately could only choose one to major in. When he is not hacking away, he enjoys catching a good game of cards, going for a swim, or of course, reading articles about awesome new innovations in science.

  • Sagnik Chakraborty

    Great article :) It will help people who do not know much about the functional elements of a PC and refer to third party advice while buying one.
    Thanks for sharing :)

  • http://kenhhoidap.com Duc Nguyen

    MainBoard , CPU , GraphicCard