What makes a computer fast and powerful?

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

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

512MB 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 Front Side Bus (FSB) 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 SSDThere are several components of a hard disk drive that 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 newer and faster 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 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 makes 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.

Additional information