Difference between Intel Core 2 Extreme / Quad / Duo vs Core i7 / i5 processors

Since its launch in late 2008, the Nehalem based Intel Core i7 processors are getting low on price and becoming mainstream processors. As a buyer, when you are searching for a PC or notebook, with Core2 range of products, now you may see Core i7 based systems are up for sale at a very competitive price.

They look very similar from their specifications, like both processors are Quad Core, operates at a similar frequency and shares almost same features like, both supports Intel VT, Intel 64, Execute Disable Bit, Speedstep Technology, Enhanced Halt State, 45mn technology and so on.

So what should you buy and why should you buy ?

Conroe (Core2) vs Nehalem (Core i7)

Core2 and Core i7 comes with a completely different processor architecture. All the available Core2 processors (Conroe, Allendale, Wolfdale) have evolved from the original Intel Core architecture Conroe where as Core i7 processors are based on a completely new architecture called Nehalem.

Processing speed and performance depends on couple of things. First the speed or rather the operating frequency second but most important the way by which it is processes a matter.

We already have seen, Intel Dual Core processor E2140 operating 1.6 GHz can out perform a Intel Pentium D 820 processors operating at 3.0 GHz while consuming less power, just because the Core architecture is much better than the age old Pentium brand.

Similar way, the Nehalem architecture is much faster and power efficient than older Core2 range.

Native Quad Core

Intel Core i7 processors have 4 native cores meaning there are 4 different cores given on a single physical die compare to Core 2 Quad where we have 2 die having 2 cores each merged together.

It allows the Core i7 processors to utilize the processor cache more efficiently than Core 2 Quad processors.

L3 Cache

Compare to Intel Core2 which comes with large L2 cache, Intel Core i7 processors include a large amount of L3 cache along with L2 also.

Core i7 processors having 256 KB of L2 for each core (256KBx4) where as a large 8 MB of L3 available as shared among all the 4 cores, is much faster thanCore 2 Quad where we have a large L2 cache is been shared between 2 dies and 2×2 cores.

Hyper-Threading is back

Yeah.. That age old feature which we have first seen in case of Intel Pentium EE processors is back with Intel Core i7. Each and every core of Intel Core i7 processors can process 2 threads simultaneously, thus appearing as a 8 core processor to the Operating system.

All though the feature didn’t click with Pentium architecture but with Nehalem it seems to help a lot with todays new multi-core based applications.

Goodbye FSB and welcome QPI

QPI is something, which is not new in market, as AMD is using it for quite some time but its something new for Intel, as finally they are saying goodbye to the traditional method of connecting various part of the CPU.

We already have seen the benefit of QPI (Quick Path Interconnect) with AMD’s Hypertransport. However, Intel’s QPI under Nehalem seems to have beaten AMD in their own game as Core i7 with QPI is much faster than AMD HyperTransport 3.0.

Adopting QPI gives Intel another great option to access memory directly via their Memory on Die Controller. As you may see, under QPI, Core i7 processor can now directly access memory as they are equipped with a memory control given directly on the processor die.

The x58 and Socket 1366

Finally after so many years, Intel replaced the socket LGA775. Intel Core i7 processor comes under a new larger socket named LGA 1366 and LGA 1156 (core i5).

Intel Core 2 platform has option to chose from many available Intel or Nvidia or ATi chipsets where as till now, Core i7 supports only one chipset, the Intel x58 but x58 seems to out perform any and every available option of Core2 platform.

Earlier one had to chose between either ATi or Nivida as platform before selecting motherboard as with Core2 you can either run SLi or CrossFire. But with x58 that problem is solved. You can run any of these multi-GPU setup from x58 or rather single motherboard.

(But that doesn’t mean you can bridge 2 different company simultaneity)

Compare to Core2 which can support both DDR-III and DDR-II, Core i7 in combination with x58 is just DDR-III only. It may sound a downer, but as DDR3 is becoming mainstream, your PC should have the fastest option.

Few new features

Intel Demand Based Switching (DBS)

Its a new form of older version, that’s Intel SpeedStep. What it does is, it lowers the processor frequency and power consumption under idle state when system doesn’t require heavy processing. The processor returns to full power only when OS requires. It saves a lot of energy and noise also as lowerfrequency means less heat hence even the processor FAN can run at lower RPM generating less noise.

Intel® Turbo Boost Technology

Performance on demand, as what Intel calls it. It allows Core i7 CPUs to actually overclock it self to run higher than its originalfrequency . Just opposite of what (DBS) does. Turbo boost works in tandem with Intel VT / Intel HT. Turbo boost actually can overclock individual cores, when they are in need of extra juice under certainly muti-core applications like heavy duty CAD / CAM or editing or virtualizing.

Along with these new features and upgrades to existing technology, Intel Core i7 or Core i5 processors make them self an excellent purchase over their predecessor. Therefore, if you are looking for a new computer with Intel based setup, try and see if you can get your self a Core i7 or Core i5 based system.

Intel Core i7 processors are available from USD 280 to $1000 where as there are hundreds of choice for motherboards under LGA 1366 and LGA 1156