Is my hardware bottle-necking my new Gtx 670?

[airborne101st45]

I just bought a Gigabyte GTX 670 like this one: http://www.newegg.com/Product/Product.aspx?Item=N82E16814125423

I upgraded from a GTS 250. I obviously noticed a difference but it doesn't feel like the card is working to its max. I am lagging in some games that my graphics card should easily max out. I think my CPU is bottle-necking my card or my hardware is just not good enough anymore (aside from the GTX 670)?

Heaven benchmark gives me over 60fps at max settings with no tessellation.

Here are my specifications:

Power Supply: 700w
Motherboard: Biostar N68S3B: http://www.biostar.com.tw/app/en/mb/introduction.php?S_ID=517
CPU: AMD Phenom II X2 550 31.GHz: http://www.newegg.com/Product/Product.aspx?Item=N82E16819103680
Memory: DDR3 Patriot AMD Performance Edition 4GB (1X4GB): http://www.kitguru.net/components/memory/zardon/amd-performance-edition-8gb16gb-memory-review-built-by-patriot/ and a similar but 2GB's only stick. http://www.newegg.com/Product/Product.aspx?Item=N82E16820103007

So is my videocard bottle-necked or is my CPU simply not strong enough to handle the newer games anymore?

Also, I think my motherboard is still running PCI-E 1.0. This affects my graphic's card performance? My GTX 670 is PCE-E 3.0. Should I buy a new motherboard?

I am going to upgrade my processor next week so I would like some suggestions on AMD processors that would run smoothly with my card. I am currently interested in the FX-6100 Bulldozer but I would need to buy a new Motherboard.

By the way, I looked at some Intel motherboards and processors and honestly they are simply out of my price range.

 

[airborne101st45]

 

[bystander]

You haven't given enough info to even know if you are having problems. Perhaps 3dmark11 at performance settings would help. Or name games or something where you may have an issue. We also need to know the resolution, and with no set standard on settings, it's hard to use Heaven as a comparison, but if you take a screen shot of the score, it may allow some of us to compare.