Question regarding how CPU and GPU work together

Will GPU be choked by a older gen CPU?

I am currently using 8800GT in SLI with

Intel Core 2 Duo E8500 @ 3.16GHz

I plan on getting ATI HD6950. Am i wasting my money because the card may be ineffective?

Or does choking of GPU only apply to really slow processors (mine seems pretty capable to me), and not to oldergen cards.

Thanks

your cpu is still great, a 6950 is a great card and won't be bottlenecked by your cpu. If you can overclock the cpu further then do so, but you should be ok.