With so many brands of desktop PCs any novice computer user can easily be confused with all that is available on the market. It is important to understand the components in desktop PCs so not only you can understand the benefits but also makes it easier to decide what you will need for your PC.

The prices of desktop PCs can greatly vary depending on the model and the company that makes them; I will not go into bare-bone systems or homemade PCs but focusing on brand PCs like HP, Acer, Apple and other various manufacturers of desktop computers. There are many components within the PC that will affect how fast the computer will run and depending on what you are using the computer for you should decide what type of components you need. The processing power of the PC is from the CPU (central processing unit) and this will affect how many and how quick your PC will process what you do. The 2 manufacturers of CPU’s are Intel and AMD and the most common processor type used in most desktops is the Dual core which has 2 processors but if you’re looking to purchase a higher end model you could get the quad core or even a hexa core which is up to 6 processors.

Moving on to the next component is the video card; this is the part of the computer that processes all of the graphics that is displayed on your monitor. You will find that some desktop PCs will have built in video cards also known as on board video. While these have improved much over the years I strongly suggest getting a desktop PC that doesn’t have on board video if you plan to play PC games. Another component which is important is the memory, also known as RAM. The memory also can play an important factor in your computers overall performance, if you like to multitask or play PC games or do anything like video editing etc… you should have at least 3GB of ram and 4GB if you buy a desktop PC with windows vista.

Another component people will use often is the hard drive this is where all of your data is stored onto. So if you like to have a lot of music, games, and other media you will need to make sure you get a large hard drive. You can also put multiple hard drives in your desktop PC as long as you do not have a mini pc case. There are many other components within the PC but I covered the components which will have more of an effect on your desktop PC performance.

source: http://ezinearticles.com/?Taking-a-Look-at-the-Components-in-Desktop-PCs&id=5211091

Introduction

Being the brain of the computer, the CPU plays a very important role in determining the performance of the system. Unfortunately, when it comes to choosing the best CPU (especially for a gaming computer), you will probably feel like a lost sheep. With different brands, models, speeds and specifications to choose from, it can really be a difficult task to decide which CPU is the right one for you.

In this guide, we give you a complete overview of what a CPU is, what are the important factors that will affect its performance and how you should go about choosing the the CPU that is best suited to your needs.

What is a CPU?

The CPU (Central Processing Unit), or sometimes known as processor, is one of the most important component in a computer system. Being the brain of the computer system, its task is to take care of all the data calculation and make sure they are processed in the fastest time possible.

CPU is not something you can see from the outside of the computer. In fact, you won’t be able to see the CPU on a fully-assembled PC. To see it, you have to remove the computer casing, unplug the wire and remove the heatsink (and fan), only then can you see the surface of the CPU. The shape of the CPU is a small square chip with lot of connector pin underneath.

How CPU works

How a CPU works is actually very simple and can be illustrated with the following 3 steps:

1. When you click to execute an application, the raw instruction is first fetched from the hard disk (sometimes from the memory) and sent to the CPU for processing.
2. When the CPU receives the instruction, it will execute the logic and compute the result.
3. Once the CPU finishes processing, it will send the result to the respective device to output to the user.

While it may seems easy, all these 3 steps must be completed in a split second. Delays in any of these steps will result in a lag in the computer, which we do not want it to happen on our gaming computer at all.

Therefore, to improve the performance of the computer, it is not enough to have a fast CPU, you still have to ensure that the transfer of information to the CPU are done in the shortest time.

Factors that affect a CPU performance

It is easy to think that the speed of the CPU is directly link to the performance of the CPU. In actual facts, this is only true to a certain extent. A CPU with fast speed will not be efficient if it has only a limited data to process each time. To achieve maximum efficiency, the hardware (especially the hard drive and memory) that linked to the CPU must supply data as fast as the CPU speed. Failure to do this will result in a lagging computer, regardless how fast the CPU is.

Below, let’s look at the other factors that affect the CPU performance.

CPU Clock Speed

The operating frequency of the CPU (also known as the clock speed) determines how fast it can process instruction.

The speed is measured in terms of Hertz, and it is usually lies in the megaHertz (MHz) or gigaHertz (GHz) range. A megaHertz means that the CPU can process one million instruction per second whereas a gigahertz CPU has the capability to process one billion instructions per second. In today technology, all CPUs run in the gigahertz range and you seldom see CPU with speed in the MHz range anymore.

Theoretically, a 500 MHz CPU is six times slower than a 3 GHz CPU. Equally, a 3.6 GHz CPU is faster than a 3 GHz or a 3.4 GHz CPU. In general, the higher the frequency of a CPU, the faster the speed of the computer.

Cache

Remember we mentioned above that for the CPU to work at its maximum efficiency, the data transfer from the other hardware must be as fast as its speed? The purpose of a cache is to ensure this smooth and fast transition of data transfer from the hardware to the CPU.

To understand how the importance of a cache, it is necessary to understand how the whole process works.The main bulk of information comes from the hard drive. When an application is requested, the motherboard will fetch the required information from the hard drive and deliver it to the CPU for processing. Since the hard drive processing speed is much slower than the CPU, data transfer often takes a long time. To fasten thing up, the RAM is used to store temporary information from the hard drive. Instead of heading straight to the hard drive, the motherboard now checks and retrieves the data from the RAM. Only when the required information is not found in the RAM then will the motherboard go to the hard drive.

As CPU speed increased to the point where the RAM is no longer able to catch up, the transferring of information again become a serious problem. To solve this issue, a cache, which was effectively a small and extremely fast memory, was added to the processor to store immediate instruction from the RAM. Since the cache runs at the same speed of the CPU, it can rapidly provide information to the CPU at the shortest time without any lag.

There are different levels of cache. Level 1 (L1) cache is the most basic form of cache and is found on every processor. Level 2 (L2) cache has a bigger memory size and is used to store more immediate instructions. In general, the L1 cache caches the L2 cache which in turn caches the RAM which in turn caches the hard disk data.

L2 cache plays the greatest part in improving the performance of the processors. The larger the cache size, the faster the data transfer and the better the CPU performance. However, cache is very costly. That is why you don’t find 1GB of cache in your system.

Multi-Core

In the past, if you want to get a faster computer, you have to get a faster CPU. Today, this is only partially true. The reason being, CPU speed can’t increase forever. There is limitation as to how fast the transistors can run and when it reaches a plateau, you won’t be able to increase the speed anymore.

To tackle this problem, CPU manufacturers (in this case, Intel and AMD) adopted a multi-core technology, which literally means putting multiple cores in a CPU chip. While increasing the CPU speed resulted in faster data calculation, putting more cores in a chip resulted in more work done at the same time.

Intel vs. AMD, Which Is Better?

You may have seen report saying that Intel is better, and on the next day, another report saying AMD is better.

You are confused…which one is better? AMD or Intel?

Both AMD and Intel CPUs are built on different circuitry and for that, it is impossible to compare apple to apple. If you were to ask me which one is better, I can only say that both are equally good and whether you choose an Intel or AMD CPU depend entirely on your preferences.

Below we will discuss the unique features of each CPU brand.

Intel: HyperThreading

Hyper threading is an Intel technology that enables the operating system to treat a single CPU as two separate CPU. In this case, the OS can split its workload into multiple threads and sent them to the two CPU concurrently. With the same amount of time spent, twice the amount of work can be done.

However, things don’t always happen as good as it sounds; HyperThreading does not necessarily lead to a performance increase. Let see why:

If you are running two pieces of software, each under its own thread, then HyperThreading can be effectively utilized to process the data simultaneously. In this case, you will see a noticeable boost in your system performance. However, in the event that there is only an application with a large chunk of data that cannot be easily split into smaller parts, the OS can only load one CPU with the calculation and leave the other idle. While this won’t cause your system to slow down, it is really a waste of resource. Such incidents are particularly true for games where all the logics are dependent to each other, and it is just not possible to split the tasks and processed with different CPU.

For HyperThreading to really increase the system performance, the software using it has to be specifically programmed for this optimization.

Hyper transport is an AMD technology designed to increase the communication speed between various components in computers. It is a completely different technology from Intel HyperThreading, but can achieve the same effect of raising the system performance. While HyperThreading serves to increase the amount of work done per CPU, HyperTransport serves to improve the data transfer process from other hardware to the CPU. What it does is to reduce the number of connection (buses) in a system, such that data can be transported from a component to another component in a shorter amount of time. This reduces the system bottlenecks and enables the CPU to use system memory more efficiently.

Core Frequency

As mentioned earlier, both Intel and AMD CPU have different circuitry and you can’t compare them apple to apple. This applies the same for their clock speed as well. If you have noticed, Intel’s speed always seems to be higher than AMD. Be careful, this does not imply that the Intel CPU is better.

The higher clocker speed simply means that there are more work cycles per second, not the amount of work done per second. Intel CPU has the tendency to divide its task into many small parts for easy processing. As such, the amount of work done per cycle is relatively small. On the contrast, AMD has lesser work cycle, but it processes more data per cycle. Thus, when it adds up, the amount of work done can be quite significant.

Unless we do benchmarking to determine the performance of each AMD and Intel CPU, it is definitely not a good idea to say that Intel is a better chip because it has a higher clock speed.

Front Side Bus

The Front Side Bus (FSB) is the communication channel that transfers data between the CPU and the other components in the system. Generally, the bandwidth of the FSB determines how much data can be transferred per second. The higher the bandwidth, the better is the system performance.

Since all the expansion cards (especially graphics card) connect to the CPU via the FSB, it is important to have a fast FSB speed to avoid any lag in the system performance.

In AMD, the HyperTransport technology has replaced the FSB with an integrated memory controller to control the data transfer to and from the components and the CPU. Due to lesser buses and more controllability, an AMD system is now able to send and receive information from various components simultaneously, and this resulted in a better performance.

Intel CPUs still use a more traditional approach, with the CPU communicating with the memory controller via the front side bus. So with Intel systems, a faster FSB often means somewhat improved performance.

Socket Type

The main reason why you can’t use an AMD and Intel CPU on the same motherboard is because they don’t have the same pin configuration. Because of the different in circuitry, the number of connection pins for both brands of CPU is also different. Even within the same brand, a specific model might use different pin configuration from another model. Thus, when choosing the CPU, it is important to bear in mind the socket type used by your motherboard.

How to Choose the Best CPU That Suits Your Needs?

For a gamer, you don’t want to have a CPU that is only good enough for word processing. What you really want is one that has a great deal of power to run the highest end games out there. While you may not have the budget to get the top end CPU in the market, you shouldn’t scrimp and get the cheapest CPU too. The more important thing is how you can strike a balance between performance and price. Here are three steps to choose your CPU.

1) Determine your budget

The last thing that you want to do is to max out your credit limit to get the most expensive CPU out there. Before you even start shopping, first determine how much money are you willing to spend on the CPU. While there is always a CPU for almost every price range, you will have to set aside about $200 for a decent gaming CPU

2) Select the brand

Choosing either a Intel or AMD CPU is really based on one preferences. Many benchmarking reports have shown that Intel score better than AMD in term of performance and heat generation, but it is more expensive. If you are low on budget, you may want to choose AMD CPU since it costs at only 3/4 of the price of a equivalent Intel CPU and still give you the performance you want.

3) Select the model

When choosing the model, focus on the no of cores, speed, and price. Check out forums/review sites to see how that particular model performs. If you are upgrading the CPU for your existing system, make sure the CPU uses the same socket as the one in your motherboard.

How to Save Money When Buying A CPU?

If you don’t have $1000 to throw around on a processor, that’s fine. There are many processors of different price range and you don’t necessary have to get the most expensive one. Here are some ways to save a few bucks.

Buy the next best processor

You don’t necessary need to get the latest processors in the market. More often than that, they are expensive and the support from other hardware is also not mature yet. You can easily save quite a bit of money simply by getting the next best processor.

Get an AMD CPU

For the same specification, AMD CPUs are generally cheaper than Intel CPUs. While many benchmarking reports have shown that Intel CPUs are better, the truth is that the differences is too small for you to notice. Using an AMD CPU for your game will not affect its performance to a great extent.

source: http://www.build-gaming-computer-guide.com/the-complete-guide-to-choose-a-cpu.html