Only when you have software that can utilize the four cores. I recently swapped my dual core for a quad running at the same frequency, and the difference was pretty subtle for most work. Also notice that on modern processors you rarely have 100% cpu load, or even 100% load on one core.
If you do computation intensive stuff, then a quad core is the way to go, but for something more data intensive that needs lots of disk accesses I would rather invest into an SSD.
True - mind you, if I have any graphics rendering / video encoding etc etc then I send it off to one of my servers - both of which have quad cores and are running Linux.
99% of the time they are sitting at idle and the other 1% of the time they are sitting at 400% ........
I am afraid my benchmark is no quite so scientific. I go by the length of time it takes my computer to load Windows XP Pro from a cold start. This is why your comments are so helpful.
Presently, I am running the E7500 with the DG43RK motherboard. I just happen to come into possession of the other components for very little money.
The chances are you wouldn't notice much difference between the two on a times windows xp bootup as the bottleneck will be with the hard drive - not the processor.