Nowadays, there are new processors coming out by the day. All these processors are 64 bit processors. This is an improvement from the previous 32 bit processors. In this post, we’ll look at some interesting facts about Intel’s Core Series processors, like i3, i5 and i7.
When I first got my laptop, I was intrigued by the specifications of my i7 processor. The seemingly miraculous computing power, which would have been unimaginable only a decade ago, now sat in a 3 kilogram machine using more memory(or in other words RAM) for its rudimentary functions than the computers of yore would use as secondary storage. Then, when I started learning about Microprocessors in my college course, I was determined to unravel the secrets of these 64 bit processors. Although, I have not been very successful in doing so, I have gained a rudimentary knowledge about its working which has slaked my thirst for now.
In this post, I will assume that you have a basic knowledge of how the x86 family works. So without further ado, I will start now.
- These processors are 64 bit processors. What this means is, their Address Bus and Data Bus is 64 bits wide. Data Bus 64 bits wide means that they can read or write 8 bytes at a time. Address Bus 64 bits wide means, theoretically, these processors can access 2^64 bytes, which is equivalent to 2^34 GB or 2^24 TB.
- Although, I did state in the previous point that they can access 2^34 GB of memory, in reality this is not so. Out of the 64 address lines, only 48 are used, the rest are not. Thus, if your motherboard supports it, and if you can buy it, you can use 2^48 bytes, that is 256 TB of RAM.
- These processors have 64 bit registers. It means that they can store and operate on 64 bit data(8 bytes long).
- They have 16 64 bit wide general purpose registers and 16 128 bit wide registers for Intel’s SSE, SSE2, SSE3,SSSE4 technologies.
- The Intel 64 architecture(i3,i5,i7) is backwards compatible with the x86 architecture.
- A common misconception is, that since a processor is 64 bit, it will be twice as fast as a 32 bit processor. It coudn’t be more wrong. The need for a 64 bit processor arose because we started dealing with numbers which were greater than 32 bits and so costly processor cycles were being wasted to fetch the remaining part of a number greater than 32 bits.
- The i3 and i5 processor have 2 cores each and 4 threads. What this means is, they have two processors and each processor has two mini processors. Basically it means that 4 processes can run EXACTLY AT THE SAME TIME.
- These processors also have 3 levels of cache. 2 levels are exclusive to each core, while the third is shared by all the cores. Cache coherency is maintained by using MESI protocol.
- These processors support a Virtual Memory of 64 TB. A page can vary from being in kilobytes, to
- Depending on whether they are first, second or third generation processors, they support 14, 18 or 20 stage pipeline.
- These processors are neither purely RISC nor are they purely CISC. They are a combination of those two.