iMac has always succeeded to make the most amazing and interesting things in the computer's technology industry. At this moment the principal characteristics of this line released by Apple Inc. at the start of 1998, are being doubled and optimized because the Macintosh line started a collaboration with the world's bigger semiconductor chip maker, Intel.
Core Duo is a line of processors covering an area of Intel's consumer 64 bit x86-64 single, dual, and quad-core CPUs founded on the Intel Core micro architecture. The single and dual core models are mono-die. On the other hand, the quad-core models are composed of 2 dies, each including 2 cores, enclosed in a protective covering of a  multi-chip module. The release of Core 2 banished the Pentium line from the high-end market to the mid-range market, and reunited laptop and desktop processor lines, which antecedently had been separated into the Pentium 4, Pentium D, and Pentium M brands. The Core Duo processor was released at the start of 2006, and was added to the iMac models after few months since Steve Jobs announced their release at the Macworld Conference and Expo, in North America.
Intel Core Duo, released under the product code 80539, comprises2 cores in one die, a 2 MB L2 cache distributed for the both cores use, and an chip that have the power to separate and to control both L2 cache and FSB access. These type of processors, also have the ability to disable one from the two cores, so that the power to be conserved. This feature is also known as CISC.
More than a half  of the desktop and Core 2 laptops processor models are Core 2 Duo with 2 processor cores on a single Merom, Conroe, Allendale, Penryn or Wolfdale chip. These come in a fully open  range of functioning and power consumption, starting with the comparatively slow ultra economic Uxxxx, with a 10 W capacity, and the economic Lxxxx, with only 17 W, models, to the more optimized and well- functioning pointed Pxxxx, with 25 W and Txxxx, with 35 W, mobile models and the Exxxx, with 65 W, desktop model types. The mobile Core 2 Duo CPUs with an 'S' prefix in the name are manufactured in a little  µFC-BGA 956 case which will allow the build of some more compact laptop models.
Among every released line, a lot of statistics refers to a better quality of products, quality that depends for the most part on core and the front side bus clock frequency and the quantity  of second level cache, that are specifically only for this model. Core 2 Duo CPU  in a typical manner use the full L2 cache of 2, 3, 4 or 6 megabytes accessible  in the specific stepping of the chip, when versions with the total of cache made bellow of normal during the manufacture process are sold for the low end consumer market as Celeron or Pentium Dual-Core CPUs. Like those processors, some low-end Core 2 Duo models make unable  features like as Intel Virtualization Technology.
Core i5, is having as base the Nehalem micro architecture. The 1st Core i5 was released on September 8, 2009 and is a almost a facsimile of the Core i7, at the beginning only quad-core desktop processors grounded on Lynnfield, with dual-core mobile, also known as Arrandale and desktop processors, Clarkdale, coming in 2010.
Intel Core i7 is a family of several Intel desktop and laptop 64-bit x86-64 processors, the 1st processors made using the Intel Nehalem micro architecture and the replacement of the Intel Core 2 family. The Core i7 signature applies to the 1st family of processors. also known as Bloomfield that was released in 2008 and  for the Lynnfield and Clarksfield models, released and sold in 2009. All the models that are currently sold on the market are quad-core processors, but the future release of Core i7-6xx "Arrandale" mobile processors, that will have only 2 cores, it is very expected.
The current Apple iMac options you can choose from those 3 types of Intel processors even it is an Intel Core 2 Duo, an  Intel Core i5, or an Intel Core i7. The graphic cards are also available in two options: nVidia GeForce 9400M integrated graphic card or an ATI Radeon HD 4670 that can be easily upgraded to the ATI Radeon HD 4850, feature that is available for the 27 inches model only. Also, the user can choose between  different dimensions of the display. One can be a 21.5 inches LCD screen or a 27 inches one, made from a glossy material.
