Buying a CPU/Processor as a Replacement Part

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Buying a CPU/Processor as a Replacement Part

The need to replace a computer's CPU, or central processing unit, or processor, is not uncommon, and while replacing faulty CPUs, or processors, is quite common, many people look for new CPUs in order to upgrade their computers to make them faster and more able. With both market leaders, Intel and AMD, continuing to release new version after new version, the computing experience is only set to grow when it comes to increasing processing speed and reducing the sizes of CPUs.

Investing in a new CPU, though, is not an easy task, given the plethora of alternatives on offer, which is why buyers should learn to differentiate between different CPUs based on aspects like cores, clock speed, front side bus, and not to forget, brands. When it comes to buying a CPU, while buyers have the option to turn to shops that deal in computer parts, looking online at websites like eBay is suggested because of the wider array of alternatives on offer. Also, while buying the latest version may seem enticing, this is something that's not really suggested.


Processors, or CPUs, in today's world come with more than just one core, which basically means that computers making use of such CPUs, in essence, have more than a single processor. The number of cores in commonly used CPUs range between two and six, although this number can go up to eight. Buyers should know that not all programs are capable of taking the advantage offered by multiple cores, so a quad-core would not necessarily offer a faster experience, depending, of course, on the program being run. Even with programs that can make use of this advantage, double the number of cores does not necessarily translate into double the speed. The table below helps illustrate the basic characteristics of CPUs with different numbers of cores.

Number of Cores



Oldest variant; still exists in some machines; no longer used in new computers; works for basic home and office use


Good for basic home and office use and gaming; not meant for newer intensive applications

Tri or quad

Ideal for gaming, image and video editing; offer reserve power

Six or eight

Meant for heavy duty computing; used with servers

All computers made available now offer CPUs with two or more cores, and when working together, they essentially help speed up the computing process. People who work with graphics or video editing, it has been noticed, favour multiple cores, and what buyers should take into account is that as the number of cores in any given brand's CPU increase, so does the price.

Clock Speed

Until the point when CPUs came only with single cores, users simply had to refer to their clock speeds to establish how fast any given CPU was. Clock speed refers to the speed of a core, is measured in Hertz, now GHz, and this still continues to play a role in how fast a computer operates. The higher the clock speed, the faster the core, and it's normally safe to assume that when different CPUs come with the same number of cores, but different clock speeds, the one with a higher clock speed should be faster. For example, a 3 GHz quad-core processor should work faster than a 2 GHz quad-core processor. On the other hand, a 3 GHz quad-core processor may well be faster than a 3.3 GHz dual-core variant, and this goes to show that the number of cores plays a more important role than clock speed. CPUs can be found with clock speed starting from 1 GHz, and extending to more than 3.5 GHz.

Front Side Bus

Front side bus, or FSB, refers to an electrical pathway found on a motherboard, which helps in connecting the CPU to various other hardware components. When compared with human physiology, if the CPU can be compared to the heart, the FSB can well be looked upon as the central nervous system, quite like helping the brain communicate with all other organs. The FSB is capable of simultaneously connecting to multiple peripherals over physical and logical sets, and it allows bi-directional flow of data. Given that fair volumes of data pass through the FSB, its speed can have a significant bearing on the overall performance of the CPU, and thereby, the computer.

FSB speed compatibility is an aspect that ought to be addressed when replacing a CPU because not all motherboards are compatible with all of the FSB speed alternatives on offer. For instance, a 1066 MHz processor cannot be used with a motherboard that supports only up to 800 MHz. On the other hand, users can install CPUs with slower FSB speeds on motherboards that support higher speeds. FSB speed depends on various factors like its frequency, the width of the bus, and the CPU's clock tick.

The Brand

This is an all-important aspect that needs to be addressed when buying a processor as a replacement part because an AMD processor does not work on a motherboard designed for Intel processors, and the reverse holds true as well. While there are certain Intel and AMD processors that perform better than others in particular aspects, these differences do not amount to much when it comes to everyday computing requirements. One aspect where processors made by these two brands vary significantly is the pricing, wherein Intel processors, when compared to their AMD counterparts, are always more expensive. While Intel processors do offer more for the money, fact remains that most everyday users don't really take advantage of their processors' capabilities.

The Processors

AMD offers a number of processors for desktops as well as laptops, and the Phenom II series is its current best offering when it comes to alternatives for desktops. These processors are ideal for advanced multitasking, high-definition entertainment, as well as video editing; and these multi-core processors are backwards compatible.

Intel's range of processors, like AMD's, comprise of entry-level alternatives, those aimed at handling mainstream applications, and high-end ones targeted at gamers and visual artists. The entry-level options comprise of Atom, Pentium, and Celeron; Core i3 and Core i5 are meant for mainstream applications; and Core i7 is the high-end alternative.

High-End Gaming Alternatives

Two of the options that buyers have in this realm include the Intel i7 2600K and the AMD 1100T. One of the key differentiating factors, as is normally the case with AMD and Intel processors, is the price, wherein the AMD processor is considerably cheaper than its Intel counterpart. The low price, however, does not imply inferior quality because the user experience with the 1100T, even when playing the latest games at high settings, can be equally good.

The Intel i7 2600K, however, does score over the 1100T in other parameters. For instance, the 1100T's higher wattage results in higher heat production, and prolonged usage ideally requires an additional aftermarket fan. Noise is also a factor that arises owing to higher power coupled with heat production, and buyers looking for the quieter alternative are better off with the i7 2600K.

32-Bit or 64-Bit?

Buyers are required to choose between 32-bit and 64-bit processors, with 64-bit processors now being offered in most modern day computers. The one key advantage of opting for a 64-bit processor is that it allows users to go beyond the 4 GB RAM mark, as this is to what a 32-bit processor limits them. Buyers who intend to indulge in professional image and video editing or hardcore gaming, as a result, should look for processors that come with 64-bit chipsets.

Other Factors

Buyers also need to establish with how much cache any given CPU comes. This cache refers to the amount of memory that comes inbuilt within the processor, which is where it stores instructions and data temporarily to prevent bottlenecks during transmission of data. The more the cache, the better it is. In addition, since excessive heat can cause damage to a processor, referring to its TDP, or thermal design power, becomes important. Higher TDP means a processor is capable of better output without the core suffering from heat damage.

Buying a CPU/Processor as a Replacement Part on eBay

When looking for a CPU to serve as a replacement part, looking on eBay presents buyers with just about every alternative that is made available in today's world, and buyers can also expect to come by alternatives that are no longer manufactured. For starters, in addition to the many alternatives offered by Intel and AMD, buyers can also look for processors made by manufacturers like Sun Microsystems, Cyrix, and VIA. The choice extends to the number of cores these processors contain, and buyers can choose between single-core processors, dual-core processors, quad-core processors, and more.

eBay gives its buyers the ability to browse through a number of manufacturer refurbished CPUs, seller refurbished CPUs, and used CPUs as well, which gives buyers the ability to save some money. Buyers can also save some money by dealing with sellers who do not charge much for postage and packaging, and there are some sellers who offer free postage as well. Looking for processors on eBay is simple; buyers can use the search box that is present on each eBay page, or they can navigate through its extensive menu system.


It is natural for people who use the same computer for prolonged periods to look for replacement processors, and in many instances, this is done in order to upgrade the machine. Buyers should know that the latest offerings are often overpriced, and these prices do not take very long to drop, that is, they go down significantly soon after the next version's release. As of now, buyers can expect to get a good deal for around 60 to 70 pounds when it comes to a mainstream processor, and around 125 to 150 pounds should suffice for a fairly decent gaming or high performance alternative.

The price alone cannot be a deciding factor, though, and buyers do need to take into account facets like the number of cores, clock speed, brand, and so on. While simple tasks like browsing the Internet, word processing, and handling simple databases can be accomplished by single-core processors, looking for a dual-core alternative is not out of place, given that the price difference is not that significant. A dual-core processor should be enough to deal with even the most intensive games, although buyers can think about investing in AMD's reasonably priced triple-core alternatives. When it comes to dealing with editing high-quality images and videos, Intel's quad-core and AMD's Phenom X4 are good starting points.

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