What to Look for in a CPU
Lately, Intel has manufactured some of the most powerful processors available commercially. Their top of the line processor is the Intel
Core i7 975 which is a quad core processor with 8 virtual cores. currently it costs about AUD$1350. It is rated at 3.33GHz which is an extremely fast processor. Intel has manufactured many dual-core CPU's as well. The latest being the E8xxx series which use the new 45nm fabrication process. I will go into this a bit later. Intel's best value for money dual core processor is probably the E8400 which is only AUD$200 and is rated at 3GHz. This is an insanely good price. Their best value Quad core processor is still the Q6600 which can now be found for less than AUD$300 and is rated at 2.4GHz.
AMD is the second largest manufacturer of CPU's. Their processors are not as fast as Intel's but offer a lot more value for money. Their best processor is the
Black Phenom II X4 3.4Ghz Quad core costs around AUD$370. This processor is better than the Q6600 because it is a native quad core processor rather than two Core 2 duo processors on one die. It however is not better than the i7 despite having a higher clock speed. This is because Intel's Core i7 have a virtual 8 cores which makes it significantly faster. The new i7's are also native quad core. AMD also has triple core offerings for those who do not want to spend excessive amounts of money on a computer but still want some decent performance. These sell at a starting price of AUD$140.
So what are the basic things you need to know about the CPU?
Intel or AMD
Well, firstly, you need to understand the differences in CPU types. CPU's have different sockets. An AMD processor will not fit in a motherboard designed for an Intel processor. Overtime, CPU manufacturers release new processors which cannot fit in an older socket on the motherboard. In a case like this, you need to replace the motherboard and possibly other parts if it is a very old computer. A good example of this is
Socket 478 and LGA 775. Socket 478 was the socket used by Intel's older CPU's such as Pentium 4 Northwood. When Intel released new Pentium 4's they also released a new socket, LGA 775. This was for various reasons such as not enough power for the CPU etc. Intel still use the LGA 775 socket which means the processor has 775 pins. People who had the old Socket 478 processor had to replace the motherboard to upgrade the processor.
intel's latest Core i7's and i5's use a new socket, LGA 1366 or 1156. LGA 1366 is for the faster Core i7's while LGA 1156 is for the lower down i7's and i5's which need less power.
Quad or Dual core
The second thing you need to understand is Quad core vs Dual core processors. Basically, a Quad Core processor is like having four processors but on one physical chip. So when a Quad Core Processor is rated at 2.4GHz, this is only the speed for one core. Dual core processors are like having two processors on one physical chip. Obviously quad core processors are better but the higher end ones are still fairly expensive. Although quad cores are faster, dual cores have their advantages. Firstly, they can access information faster. This makes it very good for games whereas a Quad core is slower but can handle multi tasking very well. These are best suited to tasks such as photo editing which requires you to have many photos open at the same time. Second, very few applications support Quad core processors, this includes games. This means that the processor will only use two cores when this application is being used. This eliminates the point of a Quad core. Quad cores, make your system future proof though as soon many manufacturers will release applications which take full advantage of Quad core processors. Eventually, all programs will utilise a quad core processor fully. This means that if you have the extra money, a Quad core is worth buying.
65nm or 45nm
The third thing you need to understand is different manufacturing processes. The difference between a 65nm fabrication process and 45nm fabrication process, is the transistors are smaller in the 45nm process. This is beneficial because it means that there are more transistors able to fit on one die and the smaller transistors are also cheaper to manufacture and require less power. This means that for the consumer, you get a cheaper processor which is a similar or a faster speed than the last generation processor. As well as this it will run cooler and be much more
overclockable. This also means the computer will be quieter and run cooler because smaller transistors require less power.
Recently Intel has announced plans to build chips around a 32nm process.
Chipset and Bus Speed
Choosing the right chipset and bus speed for the processor is also important. The chipset dictates what sort of features can be carried out by the computer. For example, older chipsets could not handle two video cards while a newer one can. The best chipset right now by Intel is the X58 chipset. For an average user, a P45 chipset is plenty and will cater for most peoples needs. Other companies which make chipsets include
Nvidia, AMD and SIS. Please look at their websites for more information. The bus speed is basically how fast data is transferred between certain points on the motherboard. The faster the bus, the faster applications will run. The bus speed can also dictate the speed of memory required for your motherboard. A general rule to follow with most Intel processors is that they are quad pumped. This means that if the bus speed is for example 1333MHz, then the actual speed you need to look at is 1333 divided by 4 which is 333.25. Then, memory is DDR which means double data rate. This means that if you multiply 333.25 by 2, you will get the speed of memory required to not cause a bottleneck in the system. In this case it is 667MHz. It is probably better though to go for 800MHz RAM if you are thinking of overclocking or even later upgrading the CPU. The reason for this is overclocking (making the processor run faster than its rated speed) raises the FSB which raises the requirements of memory. If the memory speed is too slow, bottlenecks will occur slowing the system down. This is why it is important to look at the bus speed when buying a CPU and what speed is supported by the motherboard.
There are several key elements which need consideration when you are thinking of buying a CPU. Firstly, you need to think about how you use your computer. The more games, graphics intensive programs and multitasking you do, the higher the processing speed and
L2 cache on your processor needs to be. If you are someone who only uses computers for simple tasks such as word processing and email, you only really need something like the
Intel E4xxx series which offers good general performance but tends to have a lower capacity cache which means the computer will slow down if you have many different windows open. For average users, those who do a moderate amount of gaming, some photo editing and also basic things, I think that the Intel E8xxx series is a good place to start. Even the Q6600 processor would be alright. Intel processors seem to be ahead of AMD in terms of speed however AMD were the first to develop a native quad core processor which has a high potential in the future. For high end users who play heavily graphics intensive games, a quad core processor is necessary to take full advantage of the game. The Q6600 is 2.4GHz which is alright but it gives you the most value for money. The next model up is the Q6700 which is 2.66GHz. but is almost double the price of the Q6600. Although, if you are a heavy gamer and money is not an object you would want to get one of the 45nm quad core processors. The top of the line one is the i7 975 which is coming down in price but is selling at around $1300. This is an amazing processor and is the best for gaming.
This is a basic overview of the CPU and what factors you need to consider when buying one. Think about what you use your computer for as you do not want to buy something incredibly expensive which you aren't going to use, the money is better spent on improving another aspect of your computer such as RAM. But then again, you don't want to buy something which is not suited to your needs as this is obviously handicapping your system. The CPU is not however a part to be skimped on as it significantly helps with your computers speed and usability. Not to mention it is one of the most important parts in your computer.