The two main categories of processors are 32-bit and 64-bit. These processor tells us how much memory a processor can have access from a CPU register.
A 32-bit system can access 232 memory addresses, i.e 4 GB of RAM or physical memory.
A 64-bit system can access 264 memory addresses, i.e actually 18-Billion GB of RAM. In short, any amount of memory greater than 4 GB can be easily handled by it.

32-bit processor

The 32-bit processor was the primary processor used in all computers until the early 1990s. Intel Pentium processors and early AMD processors were 32-bit, which means the operating system and software work with data units that are 32 bits wide. Windows 95, 98, and XP are all 32-bit operating systems.

64-bit processor

The 64-bit computer has been around since 1961 when IBM created the IBM 7030 Stretch supercomputer. However, it was not put into use in home computers until the early 2000s. Microsoft released a 64-bit version of Windows XP to be used on computers with a 64-bit processor. Windows Vista, Windows 7, and Windows 8 also come in 64-bit versions. Other software has been developed that is designed to run on a 64-bit computer, which are 64-bit based as well, in that they work with data units that are 64 bits wide.

Differences between a 32-bit and 64-bit CPU

A big difference between 32-bit processors and 64-bit processors is the number of calculations per second they can perform, which affects the speed at which they can complete tasks. 64-bit processors can come in dual-core, quad-core, six-core, and eight-core versions for home computing. Multiple cores allow for an increased number of calculations per second that can be performed, which can increase the processing power and help make a computer run faster. Software programs that require many calculations to function smoothly can operate faster and more efficiently on the multi-core 64-bit processors, for the most part.
Another big difference between 32-bit processors and 64-bit processors is the maximum amount of memory (RAM) that is supported. 32-bit computers support a maximum of 4 GB (232 bytes) of memory, The actual limit is often less around 3.5 GB, since part of the register is used to store other temporary values besides memory addresses. whereas 64-bit CPUs can address a theoretical maximum of 18 EB (264 bytes). However, the practical limit of 64-bit CPUs (as of 2018) is 8 TB of addressable RAM.
High amounts of RAM are especially useful for software used in graphic design, engineering, and video editing as these programs have to perform many calculations to render their images.
Advantages of 64-bit over 32-bit
  • Using 64-bit one can do a lot in multi-tasking, user can easily switch between various applications without any windows hanging problems.
  • Gamers can easily plays High graphical games like Modern Warfare, GTA V, or use high-end softwares like Photoshop or CAD which takes a lot of memory, since it makes multi-tasking with big softwares easy and efficient for users. However upgrading the video card instead of getting a 64-bit processor would be more beneficial.
A computer with a 64-bit processor can have a 64-bit or 32-bit version of an operating system installed. However, with a 32-bit operating system, the 64-bit processor would not run at its full capability.
On a computer with a 64-bit processor, we can’t run a 16-bit legacy program. Many 32-bit programs will work with a 64-bit processor and operating system, but some older 32-bit programs may not function properly, or at all, due to limited or no compatibility.

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