Buying a computer can be a lengthy process involving many complex decisions, but none come with quite as much associated technical jargon as figuring out the best CPU.
And so before you even know it, you're drowning in talk of cores and clock speeds, socket types and memory controllers, power consumption, caches and more.
While you'll need to consider at least some of these issues, there's an easier way to approach your purchasing problems. And that's to ignore the fine detail, just for the moment, and focus first on a more fundamental question: Intel vs AMD, which processors are the best for you?
You'll probably find that answering this is much more straightforward. And once you've made your choice, many other decisions about your new PC will fall into place, saving you plenty of time.
Intel vs AMD: Intel CPUs
If you're after performance above else (and you've plenty of money) then Intel processors are the way to go. At least, in general - there are several different families available and you need to be careful which you choose.
Intel Core 2 CPUs are still available, for instance, but they've been around for a long time, no longer represent a good deal and unless you're working with an old motherboard, are probably best avoided.
Instead you'll be considering a Core i3, Core i5 or Core i7 processor, which will deliver budget, mid-range or high-end performance, respectively. Except, of course, it's not quite as simple as that, because these CPUs now come in two main flavours.
The mainstream Core i3, i5 and i7 processors are available in a Socket LGA1156 package (this defines how the CPU connects to the rest of your system, and so means you'll need a Socket LGA1156 motherboard as well). This doesn't represent the very latest in Intel technology, but it's relatively reasonably priced, and there are plenty of compatible motherboards around at all price levels.
The latest Core i3/ i5/ i7 processors, code-named Sandy Bridge and available in an LGA1155 package, are rather more interesting. Not only are they up to 40% faster than their predecessors, but they also come with an on-board graphics chip, so if you're not looking for much in the way of video performance then you probably won't have to buy a graphics card.
The CPUs and Socket LGA1175 boards you'll need to run them are more expensive, but only marginally (they're still available on sub-£1,000 PCs) so if you're looking for a good mainstream Intel solution then these are the way to go.
There is a small complication, though. Intel recently identified a problem with the SATA controller in the Sandy Bridge chipset, and had to recall many motherboards. The issue is fixed now, but supplies of some boards may remain short until April, so you might have to shop around.
The other option available right now is to choose a Core i7 CPU in an LGA1366 package. This will allow you to run the very fastest 6-core Core i7 CPUs, which deliver great speeds and are very overclockable. They're also hugely expensive, though, lack extras like on-board graphics chips, and aren't actually that much faster than the high-end Sandy Bridge systems, so we'd recommend you avoid them in most situations.
Here is the main differences between AMD and Intel.
1. Intel processors usually have more LVL 2 cache memory in them. The cache memory is the absolute fastest memory in the computer. It resides in the CPU. The more cache memory that you have the better the performance will be for gaming/photoshop/music editing.
2. AMD's CPU clock speed is underestimated. If you see a Phenom II x4 running at 2.4 GHz, it will actually be running at 2.66 GHz. AMD was built from the x86_64 family of intel so they can't surpass the cache memory of Intel, but they can develop their own technology that will 'be better' than the Intel family.
3. AMD processor chipsets are programmed with ATI graphics cards in mind. They will fully utilize the ATI graphics cards. Intel processor chipsets are programmed with nVidia in mind.
There really is not a better overall processor. Although Intel has better LVL 2 cache. AMD has better LVL 3 cache that resides off the CPU, but has the technology to make it act like it is on the CPU.
Currently Intel is outperforming AMD in top of the line processors. You compare the best of AMD to the best of Intel and the Intel is about 45% faster.