The only reason to prefer 4 cores is for multitasking applications (no needed for traders) Otherwise.... the best machine you can build right now is with the Core 2 Duo E6850
Would this page on Tom's Hardware website be helpful too you... http://www.tomshardware.com/2004/05/28/getting_more_bang_out_of_your_dual_processing_buck/index.html <img src="http://www.enflow.com/p.gif">
I agree with gnome. Putting in more memory and using 10,000 rpm drives would probably benefit most traders more than a quad core would.
What does exactly mean that a dual chipset PC can share its resource between 2 x CPUs (for ex: 2 x Intel 5000 series Xeon or 2 x AMD 2200 Series Opteron) while a chipset with 1 CPU quadcore (Q6600) can't?
That's not true. It's not about 'multitasking' (I assume you mean 'multi tasking' = running several programs). It's about multi threading. One task can be divided up into several threads. If your trading platform is divided in lots of threads (each l2, chart, T&S etc in its own thread for example), then a quadcore cpu is really the cpu to buy. However, I'm quite sure that most current trading platforms are still single threaded and therefore quadcore isn't really useful. You can check out if quadcore might be useful for you: d/l process explorer: http://download.sysinternals.com/Files/ProcessExplorer.zip then see how much threads your current trading platform uses, open up a new chart/L2 and see if it adds an extra thread for it. If so, then quadcore might be useful ...
According to testers, multitasking gets a nice overall performance boost as the OS spreads single thread apps among the available cores. Biggest jump in performance is in the dual core.... smaller improvement from dual-to-quad.
Do you mean there is no great advantage switching from a Pentium D 945 OCed @ 4Ghz to a Quad6600 OCed @ 3 Ghz? (here we have more cores 4 vs. 2 but running slower although with more available 4 x 2Mb cache vs. 2 x 2Mb).