The Pentium processor still delivers great dekstop performance in low power and multitasking environments. It has dual-core technology, SpeedStep technology and execute disable bit in a 65 and 45nm package.
The Core Duo is an evolved dual-core pentium. Larger L2 cache and a faster front side bus, these processors also consume less power. Core Duo and Duo 2 improves energy efficiency and system performance by enabling smart memory access, optimized bandwidth usage and 64 bit architecture.You can deduce that the Core i5 and i7 are just enhanced Core Duo 2 processors with larger and faster cache.
The new Core i5 processers were released in September 2009. As the name would suggest, these processors do not represent a new architecture but rather a mainstream release of processors based on the Nehalem architecture, which were previously only available only as part of the Core i7 line.
Of course, the marketing of the new products indicates that they are intended to be seen as less capable products than the existing Core i7 processors. But marketing often sacrifices truth for simplicity. For example, Intel currently offers numerous products under the Pentium name, but these products are in fact Core 2 Duos and very similar to the Core 2 Duo branded products. Is Core i5 simply a marketing term, or does it indicate fundamental differences in the processor?New Socket
With a new chip Intel releases a new socket the LGA1156 and LGA1366 and a new chipset P55. They support the i line with four to six cores with or without hyper-threading.
QuickPath
This is a point-to-point high-speed links between main memory and each processor core. Available in both the Nahalem and Tukwila microarchitectures, each processor features an integrated high-speed memory controller interconnect.
Integrated Memory Controller
Designed to allow 25.6 GB/sec or moemory bandwidth through three channels of DDR3 1066 MHz, allows for lower latency and high performance for data-intensive applications.
DDR-3
The new i7 supports tripple channel memory for increased memory throughput. The i5, supports a more traditional dual-channel setup, and the difference in performance is insignificant for most users. Not to mention, the DDR-3 setup requires a greater capital investment up front.
SSE-4
The 128-bit SSE instructions are issued at one per clock cycle allowing for new levels of processing efficiency for optimized applications.
Hyper-Threading and Turbo-boost
The main difference between the i7 and i5 is the presence of Hyper-Threading, technology that simulates twice as many cores by allowing simultaneous instructions to run concurrently. For example, a Core i7 quad-core will appear in Windows as having eight cores and improves the performance of applications that make good use of multi-threading. Core i5 will not have Hyper-threading enabled but will not affect the vast majority of mainstream users.
Turbo mode is available on both the i5 and i7 which can dynamically increase the clock frequency of each processing core independently. For example, when a quad-core enters a low power state, individual cores are n longer being used, while a single core may be boosted from 2.66GHz to 3.6GHz to compensate without waking the other cores.
