Why aren’t there 128-bit CPUs?

In today’s world, we’re surrounded by cutting-edge technology, from smartphones to supercomputers. CPUs, or central processing units, are at the heart of many of these devices. They are responsible for executing the instructions that make these devices work.

A CPU’s bit count, or the number of bits it can handle at once, is a key metric in determining its performance. Historically, CPUs have evolved from 4-bit, 8-bit, 16-bit, 32-bit, and finally, 64-bit architectures. However, there has been no significant push to develop 128-bit CPUs. In this article, we’ll explore the reasons behind this.

Understanding CPU Architecture

Before diving into why there aren’t 128-bit CPUs, it’s essential to understand CPU architecture. In a nutshell, a CPU is made up of several components, including an arithmetic logic unit (ALU), a control unit, and registers.

The ALU performs mathematical and logical operations on data, while the control unit manages the flow of data between the CPU, memory, and input/output devices. Registers are high-speed memory locations that hold data that the CPU is currently working on.

One of the most critical factors in CPU performance is its bit count. A bit is the smallest unit of data in a computer and can be either a 0 or a 1. The more bits a CPU can handle, the more data it can process at once, resulting in faster processing speeds.

Why 128-Bit CPUs Don’t Exist

Now that we understand CPU architecture let’s discuss why 128-bit CPUs don’t exist. There are several reasons for this.

  1. Diminishing Returns

One of the main reasons why 128-bit CPUs don’t exist is due to the law of diminishing returns. As the bit count increases, the performance gains become increasingly smaller. This is because increasing the bit count requires more hardware, which in turn increases power consumption and heat generation.

Moreover, many of the applications that currently exist do not require more than 64-bit processing power. Applications that do require more processing power typically use GPUs (graphics processing units) rather than CPUs.

  1. Memory Limitations

Another reason why 128-bit CPUs don’t exist is due to memory limitations. CPUs with a higher bit count require more memory bandwidth to function effectively. Unfortunately, current memory technologies are not capable of delivering the necessary bandwidth to support a 128-bit CPU.

  1. Lack of Market Demand

The lack of market demand is another reason why 128-bit CPUs don’t exist. There simply isn’t enough demand for CPUs with this level of processing power. Most applications that currently exist do not require more than 64-bit processing power.

  1. Cost

Lastly, the cost of developing and manufacturing a 128-bit CPU would be prohibitive. Developing a new CPU architecture requires significant research and development, which translates to high costs.


In conclusion, there are several reasons why 128-bit CPUs don’t exist. The law of diminishing returns, memory limitations, lack of market demand, and cost are all contributing factors. While it’s possible that we may see 128-bit CPUs in the future, it’s unlikely to happen anytime soon.


Q1. Is a 128-bit CPU better than a 64-bit CPU? A1. In theory, a 128-bit CPU would be better than a 64-bit CPU as it can handle more data at once. However, in reality, there are currently no applications that require more than