For those that it's the first time this can be a confusing experience and some research needs to be done so you don't make a mistake and get the wrong CPU.
Everyone knows that there are two brands, Intel and AMD. They also know that if they go to a site like Newegg and select CPUs they will get 5 pages of CPUs , a total of close to 100 from both companies. Now what !
Intel; i3 ,i5 .i7, i7Extreme and Xeon
AMD; FX , APU and Opteron
All of these CPUs will power a computer and work very well at doing so but some are better then others at different tasks and there are many different prices.
Step 1. What is your budget for this computer that you will be building ? When building a computer you will have to decide what amount to set aside for the different components.
Step 2. What will you be using the computer for and if you are going to be doing a number of different things then you have to assign a main task so you'll know which CPU to get.
Step 3. If the computer is being used for a server or business then you want to select either the Opteron or the Xeon based on what you budget is. These CPUs are not typically used for everyday use like gaming and web surfing.
The Intel Server class CPU (Xeon)
The AMD server class (Opteron)
Step 4. An important fact when selecting a CPU for gaming is that the Intel Extreme CPUs come with 40 lanes of Pci-e bandwith which can be important to consider is your build contains more than one video card. You will notice that when examining the specs of a motherboard that the board will allocate 16 lanes of bandwith (x16) for a single card and then split those 16 lanes when two cards are used (x8 x8). With the Extreme processor you get the full 16 lanes for both cards (x16 x16) and if there were three it would be (x16 x16 x8).
This is just something to consider when building a high end gaming computer.
Tte Intel Extreme series.
Step 5. When the computer is going to be used for photo editing , video rendering or 3D graphics rendering then a CPU with more cores is needed so a AMD FX-8core or an Intel i7 with Hyper threading then provides the processing power needed.
There is the AMD FX series.
There is the Intel i7 series.
Step 6. Price plays a big part in your CPU selection as you will quickly find out when you go to look at what they cost. If your budget is low then your best option will be to go with an AMD CPU and while you may notice that in most benchmarks the AMD CPUs are behind the Intel CPUs they do still perform well in gaming and other tasks. You may even decide to go with a lower priced AMD CPU in order to get a higher model video card.
The Intel i3 series.
The AMD APU series.
Step 7. If you are strictly going with a medium range gaming computer then the best CPU for that would be the i5 from Intel and any of the FX series from AMD.
The Intel i5 series