What a System on Chip Is and Why It Matters

A System on Chip puts an entire computer on a single piece of silicon

A System on Chip (SoC) is a single integrated circuit that contains all the major components a device needs to run: the processor, memory, graphics, and input/output controls. Instead of having separate chips soldered to a circuit board, an SoC combines them into one. This is why your phone or tablet feels thin and light — there is less to fit inside.

The alternative is a traditional computer architecture, where the CPU, RAM, storage controller, and graphics processor sit on a motherboard as separate components connected by wires and bus lines. An SoC does the same job but in one package. Everything talks to everything else through internal pathways built into the silicon itself.

Most phones, tablets, and smartwatches use an SoC. Your laptop or desktop probably does not — those still use separate chips, though some newer laptops are moving toward SoC designs. The trade-off is real: an SoC is more power-efficient and compact, but harder to upgrade or repair.

Key Takeaways

• An SoC combines the processor, memory controller, graphics, and input/output into one chip instead of spreading them across a circuit board.
• Devices with an SoC use less power and fit in smaller spaces because all components are on the same piece of silicon.
• Common SoCs include Apple's A-series chips in iPhones, Qualcomm's Snapdragon in Android phones, and Samsung's Exynos.
• An SoC is harder to upgrade or repair than a traditional computer because you cannot swap out individual components.

How an SoC differs from a traditional computer architecture

In a traditional desktop or laptop, the motherboard is a platform where separate chips plug in or solder down. The CPU handles calculations, the GPU handles graphics, the RAM sits in its own slots, and a separate chipset manages communication between them all. If one component fails or becomes outdated, you can often replace just that part.

An SoC bakes all of this into one piece of silicon from the factory. The CPU cores, GPU cores, memory controllers, and I/O systems are all designed to work together on the same die. This means shorter distances for data to travel, which saves power and reduces latency. It also means the manufacturer can optimize how these parts interact in ways that would be impossible with separate chips.

The downside is that you cannot upgrade an SoC. If your phone's processor becomes slow in five years, you cannot swap it out. You have to replace the entire device. This is one reason phones and tablets have shorter useful lifespans than laptops.

Why phones and tablets use SoCs

Mobile devices benefit most from SoC design because they run on battery power. An SoC uses less electricity than separate chips because data does not have to travel as far, and the manufacturer can tune power consumption for each component. A phone with an SoC can run longer on a single charge than a phone with the same processing power but a traditional architecture.

Space is another reason. A phone is only a few millimeters thick. An SoC lets manufacturers pack a powerful computer into that space. A traditional architecture with separate CPU, GPU, RAM, and storage controller would require a much larger device.

Heat is also easier to manage. When all components are on one chip, heat spreads more evenly across the die. With separate chips, one component can become a hot spot. Manufacturers can design the SoC to distribute heat better and cool it more efficiently.

Common SoCs and what devices use them

Apple designs the A-series chips that power iPhones and iPads. The A17 Pro is in the iPhone 15 Pro, the A16 in the iPhone 14 Pro, and older A-series chips in older iPhones. Each generation adds more cores, faster speeds, and better graphics.

Qualcomm makes the Snapdragon series, which powers most Android phones. The Snapdragon 8 Gen 3 is the flagship for high-end Android phones, while lower-numbered Snapdragons go into budget and mid-range devices. Qualcomm also makes Snapdragon chips for tablets and laptops.

Samsung manufactures the Exynos series, which Samsung uses in some of its own Galaxy phones and tablets. MediaTek makes chips for budget Android phones. Google designs the Tensor chip for its Pixel phones. Apple, Qualcomm, Samsung, MediaTek, and Google all compete on speed, power efficiency, and graphics performance.

What components are actually inside an SoC

An SoC contains a CPU (the main processor), a GPU (graphics processor), a memory controller that talks to the device's RAM, and an I/O controller that handles connections to the screen, microphone, camera, and wireless radios. It also includes a neural processing unit (NPU) in newer designs, which speeds up artificial intelligence tasks.

The CPU is usually made of multiple cores — a flagship phone SoC might have eight cores split between high-performance cores for demanding tasks and efficiency cores for background work. The GPU has its own cores optimized for graphics and video. The memory controller is the traffic cop that decides what data goes where and when.

The I/O controller is what lets the SoC talk to everything else in the phone: the display, the battery, the camera sensors, the microphone, the speaker, and the wireless chips for cellular, Wi-Fi, and Bluetooth. All of these connections run through the I/O controller.

SoCs in laptops and desktops

For years, laptops and desktops used traditional architectures with separate CPU and GPU chips. Apple changed this with the M1 chip in 2020, which was an SoC designed for laptops. The M1, M2, M3, and newer M-series chips are now in all MacBooks. They offer better battery life and performance than Intel chips in comparable laptops.

Most Windows laptops still use separate Intel or AMD processors paired with separate graphics chips. However, Intel and AMD are moving toward SoC designs for laptops too. Intel's newer Core Ultra chips and AMD's Ryzen AI chips combine the CPU and GPU on one die, similar to what Apple did.

Desktop computers almost never use SoCs. They prioritize upgradability and raw performance over power efficiency. A desktop user might want to swap the GPU for a better one, or add more RAM, or upgrade the CPU in a few years. An SoC makes all of that impossible.

Trade-offs: efficiency and size versus repairability

The main advantage of an SoC is efficiency. Less power consumption means longer battery life in phones and tablets. Smaller size means thinner, lighter devices. Better thermal design means less heat and less need for cooling fans. These are real benefits that users notice every day.

The main disadvantage is that you cannot repair or upgrade an SoC. If the processor fails, the entire chip fails. If you want a faster device, you have to buy a new one. This is frustrating for people who want their devices to last longer or who want to fix them themselves. It also means more electronic waste.

Some manufacturers are starting to design phones and tablets with replaceable components, but this goes against the SoC trend. A device with a replaceable SoC would be thicker and heavier and use more power. The industry has decided that most users prefer thin, light, efficient devices over the ability to upgrade.

Frequently Asked Questions

Is an SoC faster than a traditional CPU and GPU?

Not necessarily. Speed depends on the design and the number of cores, not on whether components are on one chip or separate. An SoC can be faster because data travels shorter distances, but a high-end desktop CPU can still outperform a phone SoC in raw processing power. They are optimized for different things.

Can you upgrade the RAM or storage in a phone with an SoC?

No. The memory controller is built into the SoC, and the RAM is soldered directly to the circuit board. You cannot add more RAM or swap it out. Storage is also usually soldered down. This is why you have to choose your phone's storage size when you buy it.

Why do some laptops still use separate CPU and GPU chips?

Desktops and some laptops prioritize performance and upgradability over power efficiency. A separate high-end GPU can be swapped out for a better one. A separate CPU can be upgraded. An SoC locks you into one configuration for the life of the device. Gamers and professionals often prefer the flexibility.

Do all phones use an SoC?

Yes, all modern smartphones use an SoC. This includes iPhones, Android phones, and any other smartphone. The SoC design is standard for mobile devices because of the power and space benefits. Tablets also use SoCs, usually the same ones as phones.

Will desktops ever switch to SoCs?

Unlikely for high-performance desktops. Gaming and workstation users need upgradeable components. However, small form-factor PCs and all-in-one computers might move toward SoC designs in the future if manufacturers decide the trade-off is worth it.