is xp pro capable of using quad core

Can anyone tell me for a power user with lot of multitasking, will Windows XP benefit from using Quad Core like for example Intel core 2 quad Q6600? Also, what about the current computer with dual core cpu replaced by a new quad core, does anyone have to do anything besides reactivating the operating system? Thanks.

You will not notice too much if the applications you have will not utilize it. If you have a motherboard then all you need to do is change CPUs, you will not even have to run a repair installation or activate OS again.

Thanks for the reply, so you mean to say that Windows XP will only be able to use atmost 2 cores that is the limitation of the OS? What is the limit of Vista OS then?

Windows XP will be able to support 2 processors without any issue, the number of cores are usually irrelevant.