What makes a computer fast and powerful?

Updated: 11/13/2018 by Computer Hope

Note: This document helps explain the components within a computer that help make it fast. See our troubleshooting a slow computer page if you need help troubleshooting a slow computer.

There are several components within a computer that help make it faster and overall more powerful. Below is a list of the main hardware components that help contribute to the performance of a computer. Keep in mind that open and running software may also impact the speed of a computer.

Processor (CPU)

Computer CPUThe overall speed or clock speed of the computer and how fast it is capable of processing data is managed by the computer processor (CPU). The computer will be much faster and more powerful when it is capable of executing more instructions every second. For example, the first computer processor was the Intel 4004, which was only a 740 kHz processor and capable of processing approximately 92,000 instructions per second. Today's processors are multi-core GHz processors capable of processing over 100 billion instructions per second.


Although today's computers can execute billions of instructions every second, the processor is usually waiting for those instructions from the slower types of memory in the computer. Because RAM and the hard drive are slower than the CPU, computer processors and motherboards use cache to transfer data between the processor, memory, and components in the computer. Cache is the fastest type of memory, and a computer with more L2 cache or L3 cache is capable of storing more instructions and send those instructions to the processor more efficiently.

Memory (RAM)

A computer with more memory (RAM) will be capable of storing more programs that are currently running in memory. If your computer runs out of memory, the computer must swap unused data stored in memory to your hard disk drive until it is needed again. By adding this extra step and because the hard drive is the slowest type of memory, your computer can become much slower if it does not have enough memory.

512 MB memory stick

BUS speed

The bus speed of the motherboard can increase or decrease the speed at which data is being transferred between all the hardware components in the computer. For example, a FSB (front-side bus) of 66 MHz is going to be much slower than a 400 MHz FSB. If the computer has a slow bus, the processor has to wait longer for the instructions, which makes the computer run slower.

Hard drive

Crucial SSDSeveral components of a hard disk drive can make it slower or faster, which makes your computer run slower or faster overall.

For example, a hard drive can cause a computer to be slower because of the moving parts inside the hard drive, which results in slower read and write times from and to the hard drive. However, a solid-state drives (SSD) have no moving parts, which results in faster read and write times from and to the hard drive.

Below is a list of different factors that contribute to the speed of a hard drive.

  • An SSD drive has no movable parts, which makes it much faster than a traditional HDD.
  • Older computers use EIDE (ATA) cables and ports to connect the drives, which have a much slower transfer rate than the SATA cables and ports used in newer computers.
  • The RPM of the HDD is how fast the platters inside the hard drive spin. A 5400 RPM hard drive will be much slower than a 7200 RPM drive.
  • Since the cache is the fastest type of memory, a hard drive with a larger cache allows data to be handled more efficiently when it's transferred between the computer and the hard drive.

Video card

If you play the latest computer games, a powerful video card with its own CPU (GPU) and its own memory make the game run faster. These types of video cards help with the performance of the computer by taking on the responsibilities of processing the 3D rendering and other complex tasks. The more powerful the video card is, the better it can render the 3D graphics and the faster it can handle the overall processing of graphics for the game.

The interface of a video card is also a contributing factor to the performance of the video card. For example, older AGP video cards are much slower than newer PCI Express video cards.

Latest operating system

In addition to the hardware that runs on your computer having the latest operating system can have a significant impact on your overall computer's performance. As new technologies are introduced for them to be fully supported by a computer, the operating system must also be written to interact with those new technologies. Although today's operating systems release updates to support new technologies, older operating systems may not receive these updates. For example, a computer with Windows XP will run slower than a computer with Windows 10 because it not only supports all the latest hardware, the computer also has more recent technology.


The software you're using can also affect the speed of a computer. If the software is not written to be efficient or if there are bugs with the software, it can cause your computer to run slow while those programs are being used. If your computer runs slow while running a program, make sure you have all the latest updates for that program.

Using the latest technologies

A computer that is using the latest technologies is going to be much faster than a computer that is using older technologies because new technology always increases the speed and efficiency. If you're using a computer that is 10+ years old, it's going to be much slower than a computer that is less than a year old because it is using the latest technologies. For example, a SATA SSD (mentioned earlier) in a computer today will run much faster than a 5400 RPM IDE hard drive.