Evaluating Tablet PCs Based on Processors

A tablet's processor can offer clues about speed and function

When purchasing a tablet, most people don't think about the type of processor, or CPU, it has. However, the CPU for a tablet determines how fast it is and what types of apps it can run, so you should know how to tell if a tablet's processor is up to the tasks you need it to do.

Information in this article applies broadly to tablets made by various manufacturers (Google, Apple, Samsung, etc.).

What Is a Good Processor for a Tablet?

The brand or architecture of a processor doesn't matter as much as its technical specifications, specifically its speed and the number of cores it has. The processor usually plays a key factor in the price of a tablet. The most powerful tablets on the market today, such as the Microsoft Surface Pro 7, boast octa-core CPUs with processing speeds over 2 GHz.

If you only need a tablet to read books and browse the web, you can find budget tablets that have enough processing power for those purposes. If you want to use a tablet to play 3D games or do graphic design work, then a higher-end CPU is a necessity.

NVIDIA Tegra 4 Processor
NVIDIA Tegra 4 Processor. ©NVIDIA

ARM Processors

Most tablets use a processor architecture produced by ARM, a company that designs the basic processor architecture and then licenses those designs out to other companies to manufacture. As a result, there are similar ARM-based processors manufactured by a wide range of companies. For example, while iPhones use a proprietary CPU made by Apple, it is based on the ARM architecture.

The most common ARM processor design for tablets is based on the Cortex-A. These designs are considered systems-on-a-chip (SoCs) because they also integrate the RAM and graphics into a single silicon chip. This has some implications, as two similar chips' processor cores may have different amounts of memory and different graphics engines, which can cause variations in performance.

Manufacturers might alter the design slightly, but for the most part, performance will be very similar between products within the same base design. The actual speeds can differ because of the amount of memory, the platform's operating system, and the graphics processor. However, if one processor is based on the Cortex-A8 while another is based on Cortex-A9, the higher model will typically offer better performance at similar speeds.

Below is a list of Cortex-A models and their features:

Processor Description Cores Speed
Cortex-A5 Lowest power consumption Generally single-core Clock speeds between 300 and 800MHz
Cortex-A8 Modest processor with better media performance than A5 Generally single or dual-core Clock speeds between 600MHz and 1.5GHz
Cortex-A9 Most popular of the processors Typically dual-core but available with up to four Clock speeds between 800MHz and 2GHz
Cortex-A12  Similar to the A9 but with wider bus paths and improved caching Available with up to four cores Clock speeds up to 2GHz
Cortex-A15 32-bit design Typically dual or quad-core Clock speeds between 1GHz and 2GHz
Cortex-A17  Newer more efficient 32-bit design similar to the A15 but with slightly better performance Up to 4 processor cores Clock speeds between 1.5GHz and over 2GHz
Cortex-A53 The first of the new 64-bit processors Has between one and four cores Clock speeds between 1.5GHz and over 2.3GHz
Cortex-A57 Higher power 64-bit processor intended for consumer electronics and computers more than tablets Has between one and four cores Clock speeds up to 2GHz
Cortex-A72 Latest 64-bit processor, intended for consumer electronics or PCs rather than tablets Has between one and four cores Clock speeds up to 2.5GHz

x86 Processors

Tablets that run Windows typically use x86-based processors since Windows was written for this type of architecture. The two major manufacturers of x86 processors are AMD and Intel.

Intel x86 Processors

Intel is the most frequently used of the two, thanks to its low-power Atom processors. They may not be as powerful as traditional laptop processors, but they still provide sufficient performance for running Windows, albeit somewhat slower.

Intel offers a wide range of Atom processors. The Z series, found in older tablets, has a long battery life but is relatively slow.

A newer X series of Atom processors was released that offers greatly improved performance over the past Z series with just as long or longer battery life. If you are looking at a tablet with an Atom processor, it is best to look for one with a newer X5 or X7 processor. If it uses the older processor line, try to get the Z5300 or higher.

There are also tablets that use the energy-efficient Intel Core series. Such processors offer a similar level of performance, but they generally are not as compact as the Atom-based processors. The Core M series of processors also offer performance somewhere between the Core i5 and the Atom processors. They are well suited for tablets since some models don't require active cooling.

Intel has rebranded newer versions of their Intel Core processors with 5Y and 7Y model numbers.

AMD Processors

AMD offers several processors based on its APU architecture, which is just another name for a processor with integrated graphics. There are two versions of the APU that could be used for tablets. The E series was the original design meant for low power consumption. The more recent offerings are the A4-1000 series, which are ultra-low wattage and can be used with a tablet or 2-in-1 hybrid laptops.

How Many Number of Cores Is Enough?

Higher-end tablets feature multiple core ​processors to improve multitasking. With multiple cores, the operating system can better allocate tasks to help speed up performance. That way, you can listen to music and play a game at the same time without one affecting the other.