HD5850 v Q6600 Bottlenecking?

[shaunk]

My system:
Asus Maximus Formula x38
Intel Q6600 (@3.0ghz)
4x1GB DDR2
3 x 150GB WD Raptors (RAID 5)
HIS HD5850 1GB
Corsair HX620w PSU
Antec 300 case
Win7 x64

I've been upgrading and tinkering with this system since I first built it several years back but I've been starting to wonder if I might have reached the point where my CPU (which I'm very fond of) might be bottle-necking my GPU performance. Obviously mid-high end graphics cards aren't cheap and I don't want to be losing value from them due to the aging base of my system. Any well informed opinions on this are welcome, as well as any suggestions on an economical upgrade if its necessary. (Bearing in mind this is Socket 775 so a motherboard replacement and a move to DDR3 would probably be a necessary added expense.)

 

[shaunk]

I should add that I game at 1680x1050 and I do have a spare 512mb 8800gt that has a few overheating issues but may well do as a Physx processor if I were to move to an Nvidia card.

 

[AbdullahG]

There is really no bottleneck present. The Q6600 is still a CPU that performs very well. With some OCing, you should be fine (though not necessary).