Which brand CF Card is fastest?

I have a 40D and use a 4GB ATP ProMax CF Card. The capacity is fine, but I'm wondering if there are faster cards available. I don't really use multi-shot mode, so it probably doesn't make too much of a difference, but I am curious.

Another question: occasionally a picture on the card cannot be read (or transferred to my PC). It shows up on the LCD as a small icon with an error message ("cannot be read" or similar). Do any of you ever experience the same behavior? Do you think it's the card I'm using????

Thanx, Jim

Sounds like a bad card. Check the Rob Galbraith CF Database for fast cards on the 40D.

Lexar 600x UDMA I would guess?

The 40D can't take advantage of UDMA cards (although it will work with them). So, unless you have a UDMA enabled card reader there's little point in getting a fast card. However, it is a good idea to have a reliable card - so I'd junk the one you're using.

SanDisk?

I'm using the "cheapie" 32Gb card from ridata and that does the trick for me. I was shooting Hi-Def movies, 8fps bursts, e.t.c....and it doesn't slow down the file transfer for me. So, from my experience, anything 133x and higher would do the job.

Here are some high end card tests you may want to check out [Link]. I ordered a Photofast GMonster 64gb last night since it still seems plenty fast and enough capacity to shoot RAW all day in either my 5DmkII or 1DmkIV.

(edit: misread post, thought he had a 1D... long day)

If you're having card problems, or even think you might be, reformat the card in your camera (not on your PC or in another camera).

I run nothing but Sandisk, I would say they are the most reliable ive heard

I'm using Lexar Pro 300x cards in my 50D. They seem to be pretty fast (around 30mb/s or so) and can't say I have had any issues with them in terms of reliability.

None of my cameras are UDMA enabled, but i'm using the Sandisk 8GB 30mb/s "Extreme III" cards that were rebadged as "Ultra"