Could someone tell me about dual core processors?

Question

I pretty much need to know anything and everything you can tell me about them. the difference in type. why the procesing speed seems lower than industry avg. yet i hear they are faster. The type of motherboard that you need to buy .. etc etc etc

thanks

Answer 1

A multi-core microprocessor is one that combines two or more independent processors into a single package, often a single integrated circuit (IC). A dual-core device contains two independent microprocessors. In general, multi-core microprocessors allow a computing device to exhibit some form of thread-level parallelism (TLP) without including multiple microprocessors in separate physical packages. This form of TLP is often known as chip-level multiprocessing.

There is some discrepancy in the semantics by which the terms "multi-core" and "dual-core" are defined. Most commonly they are used to refer to some sort of central processing unit (CPU), but are sometimes also applied to DSPs and SoCs. Additionally, some use these terms only to refer to multi-core microprocessors that are manufactured on the same integrated circuit die. These persons generally prefer to refer to separate microprocessor dies in the same package by another name, such as "multi-chip module", "double core", or even "twin core". This article uses both the terms "multi-core" and "dual-core" to reference microelectronic CPUs manufactured on the same integrated circuit, unless otherwise noted.

Advantages

* Proximity of multiple CPU cores on the same die have the advantage that the cache coherency circuitry can operate at a much higher clock rate than is possible if the signals have to travel off-chip, so combining equivalent CPUs on a single die significantly improves the performance of cache snoop (alternative: Bus snooping) operations. In simpler words, it means that because the signal between different chips has to travel a shorter distance, it does not degenerate as much, which allows more data to be sent at the same period of time - as individual signals can be shorter and do not need to be repeated as often.
* Assuming that the die can fit into the package, physically, the multi-core CPU designs require much less Printed Circuit Board (PCB) space than multi-chip SMP designs.
* A dual-core processor uses slightly less power than two coupled single-core processors, principally because of the increased power required to drive signals external to the chip and because the smaller silicon process geometry allows the cores to operate at lower voltages; such reduction reduces latency. Furthermore, the cores share some circuitry, like the L2 cache and the interface to the front side bus (FSB).
* In terms of competing technologies for the available silicon die area, multi-core design can make use of proven CPU core library designs and produce a product with lower risk of design error than devising a new wider core design. Also, adding more cache suffers from diminishing returns.

Disadvantages

* In addition to operating system (OS) support, adjustments to existing software are required to maximize utilization of the computing resources provided by multi-core processors. Also, the ability of multi-core processors to increase application performance depends on the use of multiple threads within applications. For example, most current (2006) video games will run faster on a 3 GHz single-core processor than on a 2GHz dual-core processor (of the same core architecture), despite the dual-core theoretically having more processing power, because they are incapable of efficiently using more than one core at a time.[1]
* Integration of a multi-core chip drives production yields down and they are more difficult to manage thermally than lower-density single-chip designs.
* From an architectural point of view, ultimately, single CPU designs may make better use of the silicon surface area than multiprocessing cores, so a development commitment to this architecture may carry the risk of obsolescence.
* Raw processing power is not the only constraint on system performance. Two processing cores sharing the same system bus and memory bandwidth limits the real-world performance advantage. If a single core is close to being memory bandwidth limited, going to dual-core might only give 30% to 70% improvement. If memory-bandwidth is not a problem a 90% improvement can be expected. It would be possible for an application that used 2 CPUs to end up running faster on one dual-core if communication between the CPUs was the limiting factor, which would count as more than 100% improvement.

Answer 2

It's just a newer technology. The chips have been engineered to do more per CPU cycle as opposed to needing a higher operating frequency. You can find more information about chips offered by Intel and AMD by going to the manufacturer websites.

www.intel.com
www.amd.com

In reference to mainboards. Most resellers have charts you can look at to match the board to the processor. You can also call a reseller and ask them.