on 07-05-2007 05:27 AM
As was already mentioned if your software doesn't support it, you woun't really gain any benefit.
However games such as Crysis will run much faster on a Quad core, presumably for the same reasons Unreal Tournament 3 will run faster, each core take control of different parts of the game.
So for instance, core 1 might run the actual game code, core 2, the A.I, core 3 the Physics, core 4 the Graphics. I think that's more or less how Tim sweeney said the UT 3 would benefit from a Quad core.
As for the existing motherboard, you might get a BIOS update that enables Quad core, or you might not. You might be better taking the plunge and getting a board designed to work with Quad core out-of-the-box.
Also Intel and AMD Quad cores differ. Intel's are basically 2 Core 2 Duos side by side where as the AMD chips are truly independant of each other and don't share system buses (or something like that!) which means they will probably perform better than the equivalent Intel offerings.