What is better for PC gaming Dual Core or Quad Core?

i have a Intel E5400 Overclocked to 3.23GHz and was going to upgrade to a Q9400 quad and was wondering as i mainly use my PC for high end gaming is quad core as important as it is used more for multitasking and i was told dual would be better for gaming is this true?

It's a little confusing. I'd say in general, quad-core processors are more powerful than dual core; however, that doesn't necessarily mean faster.

Certain programs are written to take advantage of multi-core processors, like many games and power-hungry programs such as Photoshop.

However, not all are. Windows does its best to distribute the load evenly, but it's not the same.

Furthermore, many quad core processors are clocked at a lower rate than dual core. Your dual-core processor is clocked at 3.23GHz; the quad is clocked at 2.66.

Bottom line: if the programs you will be running can make use of all the cores, you will very likely see a performance increase. If they are not designed that way, there is a good chance your performance will actually decrease.

In your case, I suspect the programs you will be running can make use of the 4 cores well; many games do. But use your judgment!

Depends on the Game and the speed of the processor. If you go to a Quad at a lower speed than your Dual and the game doesn't support Quad core threads, then you will be running the game with 2 cores slower than your Dualcore CPU. But other processes in Windows can still run in the other cores, so you still might see improvements. Just depends on the speed and game (and I guess, what you are doing in this case multi-tasking while in game).

Also, more games are programming towards using Quad cores, like Battlefield BC2.

Quads are better for gaming with games that can use all 4 cores like Crysis. Quads are also much more difficult to get stable when overclocking and can run hotter than a dual core so it's a trade off.

Quads also take more work to get stable but are worth the extra effort and are better for gaming in my opinion. I have had both the E8600 at 4.275 - 4.5GHz and my Q9650 which sits at 4.05GHz but can easily do 4.275GHz, I like the quad better for gaming, seems to be smoother for me when I run Crysis enthusiast settings 2XAA.

Thanks for all the advice i thought quad core would improve my experience but was told that dual was better i think i will probably just upgrade to the quad then as it should improve speed and game play.

just got my quad and still use my dual. not much more speed in my quad but the graphics are pretty good. i have an ATI card in this one but i have been nividia guy. it's a better gaming experience useing the quad, of course with a better system all around to support it. i play Unreal(all of them)MW2, COD4, and Battlefield bad company2. although BBC2 sucks cause it don't have a free for all/DM mode.