At 04:39 PM 2/9/2007, you wrote:
>What is the advantage of having dual processors instead of a single
>processor?

Dual processors, and now dual core, which you can think of as two 
processors in one package, will give you a faster multitasking 
experience. Which means, you can run more things simultaneously 
without taking a performance hit. No poorly coded, or misbehaving 
application can bring your computer to a halt because the other 
processor is available to allow you to shut it down, or to solve the problem.

There is also a hair trigger feeling to working with multi processor 
workstations that can be addictive.  Dual processors can make 
applications run much faster if the operating system supports multi 
processors, ( Windows NT, 2000, XP PRO all support SMP = Symmetric 
Multi Processors ), and if the application is written to support 
SMP..... few are. Typically high end professional applications do. 
Things like Adobe Photo Shop, Adobe Premier, Auto CAD, any 
professional application that requires a lot of number crunching.

Games might be able to benefit from SMP but non are written for it 
yet.  However, now that dual and even Quad Core have entered the 
desktop market you can expect to see many, many more applications 
written to support dual or multi core processors.

Two 3 Ghz processors do not deliver 6 Ghz, or even 4 Ghz performance. 
You can not run faster then the speed of the processors = 3Ghz. 
However, as a rule of thumb you can figure in result, using supported 
programs, about 75 per cent of the speed of the combined processors 
may be achieved. It all depends on the operating system and the 
programs coding. Higher results are available in other operating 
systems, such as Unix.

To give you an example of what can be done, I use a program called 
TMPgEnc to encode video. It fully supports SMP running on XP PRO SP2. 
I am using a Dual Xeon 3.06 Ghz 533 FSB computer.If I encode the same 
video file, on the dual Xeon, and on a P4 3.4 GHZ  800 FSB, the dual 
Xeon takes about 30 minutes while the single P4 takes about 50 minutes.

Rode
The NOSPIN Group
http://www.freepctech.com/rode/ 

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