Quad Core Gaming Pointless? Waste of Money?

Okay honestly I am not sure but, from the gaming aspect I see quad core as a marketing thing for gamers... in otherwords really overrated, and I kind of find it weird that it took me this long to figure it out on my own, I probably was blinded by all the marketing of manufacturers like alienware. Just take a look at their systems on their website http://alienware.com/product_pages/desktop_all_default.aspx ... they're all mostly quad core.

I haven't heard of many games that are optimized to run on Quad Core Processors hell even 8 core systems. In fact I beleive alot of games run better on Dual Core processors as opposed to Quad and so forth.
Its kind of like spending money on a Ageia physX card that only is designed to run with a handful of certain games.
I can get a powrful gaming system for the price of some of these Quad Core proccesors.

Does anyone disagree or agree?
or know any games that are optimized to run with a 4 or 8 core CPU? - I only know one or two.

Well I have looked for a single core CPU... and the best one out there I have so far found is the AMD Athlon 64 4000... not sure if its 4ghz...

http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=2877777&CatId=1949

Unfortunately I can't find any motherboards that have a 939 socket and a PCI express 2.0 slot, not that I want SLI, but, not sure what's the fastest graphic card I could combine with that... 6800 ultra?

Also another question... does the chipset ie. the 790i ultra make any huge difference in gaming performance compared to older chipsets? or is that another marketing scheme?
ie. 790i ultra chipset only adds support for quad sli.