Hi all. I've been looking around, and have been unable to decide whether I want a Q9450 or an E8500. My rig is mostly used for gaming, apart from the usual web browsing, email, word processing, etc. I've gathered that at the moment a speedier dual core beats quad core for gaming, but it seems that soon quad core could become more important for gaming. I do intend to overclock, and I probably won't upgrade for at the very least another 2 years. Any help would be much appreciated

Thanks,
DG

[EDIT] I sort of left this to the last moment, and need to order today, for various reasons, so any help before then would be great

Regarding upgrading in 2 years.. Intel's new generation chip Nehalem will require an entirely different socket, motherboard, and RAM (DDR3).  Intel is moving the memory controller from the northbridge to the die and will be phasing out the aging front-side-bus altogether.  What this means is that in 2 years when you're ready to upgrade, you will be purchasing a new motherboard and RAM along with your processor.  Intel's E8xxx and Qxxxx series are the last in line of their LGA775 socket chips.

If you are okay with knowing you will need to upgrade a lot more than your processor in 2 years, then I'd say go with the E8500 for gaming as it will beat the quad in this area.  It also has a 9.5x multiplier, so it should overclock well.

If you are looking for longevity of your system (more than 2 years), then go with the quad.  If you clock the FSB to 400 (mild overclock), your quad will run at 3.2 Ghz which is slightly better than the E8500 at stock.

Games will still take awhile to adopt multi-core support.  Maybe a few games over the next year.  I think even Crysis only utilizes 2 cores for now.

Yes fast dual cores perform better than the quad atm..it will change in the future for sure...quads are MOSTLY useful for vid editing...you haven't mentioned vid editing...E8400 is surely a great CPU..overclocks very well too...get it if its urgent. You wont be disappointed. Or if you can wait, then wait for the q9450 to release.

At the level of the E8500 or Q9450, the vga card is much more important for gaming than the cpu.  At that level, overclocking is good for bragging, but it will not net you as much increase in FPS as a better vga card will.  Today, very few games can make use of more than two cores.   Flight simulator X is an exception.   It is not a trivial matter to code multi threaded programs, and game vendors will not sell too many games that require quads to run.   I don't see this changing in the next couple of years, and then nehalem will be upon us.
 
Net:  E8500 for the increased clock speed.
 
Also, go to 4gb, ddr2 is cheap, and it insulates the game from interference while multitasking.
 

How much do you plan on overclocking?  Duals overclock better, but if you're going for mild/moderate, then either will do.  I agree with the 2nd post, Intel's next new chips coming out will be on a whole new platform.  Qwertycopter give a brief but truthful aspect of the next-gen platform.

This sounds like a job for the E8500, unless you're a big fan of FSX.

Thanks loads, everyone
 
How much do I plan on overclocking? Well as far as I can stably get it without upping the heat or voltage too much: even if I am going to have to essentially build a new rig when I upgrade in 2-3 years, I'd like to avoid burning anything out and keep my current components as spares, so I won't just ignore heat and voltage, but I'm not averse to a bit of an increase here and there