Dual core processor performance can be influenced by so many factors
It is really not accurate to simply state it will be twice as fast as a single core processor.
Operating systems such as Windows 2000 – XP and Vista all support multithreading meaning that they will support multi core processors, but this has never been a problem, the issue has always been with the applications that run under this,
For example Microsoft Office 2003 will only support single threading so no matter which processor you have it will in effect only function as a single core processor as the software will only support one of the cores.
The later generation of processors are very good and even running on a single core is still better than many of the older processors, but amount of processing power is almost halved here.
So if you are into heavy duty spreadsheets you will really need to be using Office 2007 which has full support for multi core processors. ( it even has a great little option so you can specify the amount of cores it should use ) one test that we carried out on an Excel report, on a Quad core pc running under XP with Office 2003 was taking just over 4 hours, running the same test on the same pc using Excel 2007 was taking less than 30 minutes, this always shows the efficiency of Excel 2007.
In a nutshell if you have a game or application that runs little or no faster than on your old pc the chances are it does not support multiple threading.
A simple test for this is to open task manager – making sure you are viewing one CPU per graph so you get a view of each processor/core launch your application and then check with task manager on the CPU usage under the Performance tab and see if both cores are being used.
As above both CPU cores can be seen.
Make sure CPU history and One Graph Per CPU is selected if your current view is different
If not it is always worth checking to see if developers of the software have released a patch to make multiple threading compatible with the software.
Generally in most cases though, such as Office 2003 they would prefer you purchase the later version, so no patch is usually available.
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