What is the fastest practical CF card write speed for a Nikon D700?

I have a Nikon D700 and am wondering at what, if any, write speed I would be wasting my money on a faster CF card. I hope that makes sense. What I mean is that, if the D700 is only capable of writing to a CF memory card at a maximum rate of 45 MB/second, it doesn't make sense for me to spend a premium on a 60 MB/second CF card. If there's a cap on the D700's write speed regardless of storage medium, what is that cap?

Just buy the fastest available, you won't be waisting your money. If you can afford a $2, 600 camera you can certainly afford 3 or 4 of the fastest CF cards available.

The D700 is compliant with UDMA cards (fast read/write).

That means that a 266x card can be used.

I fail to see why you would need such a fast reading card unless you intend to shoot at 5 fps until the memory card is filled. Usually before something like that can happen, the cameras buffer will fill and shooting will temporarily stop. How many shots you can shoot at that rate will have more to do with the resolution you are using

Frankly the fact that you are using a full frame camera, using less than full resolution in the RAW + JPEG mode seems to be silly

Rob Galbraith has a database for this stuff. The fastest you'll get on a D700 is 30MB/sec.: http://www.robgalbraith.com/bins/camera_multi_page.asp?cid=6007-9550

The test is perhaps dated but you get the point - the D700 tops out at 30MB/sec using much faster cards.

So when you're blasting away with the grip at 8FPS in RAW and/or JPG large + fine, you'll invariably clog up the buffer in no time. If you need a sports camera, get a used D3 and send to Nikon for the $500 buffer expansion (which doubles the buffer, bringing it to the standard size of the D3s' buffer.) Or spend extra and get the D3s for the better high ISO performance, to boot. The buffer upgrade is not available for the D700.