If it's agp the clip won't be in the way when you insert the card. If it's agp pro it will be in the way and you'll have to remove it. agp pro is longer.
Edit: AGP Pro extends the existing AGP connectors on both ends to deliver additional power on the 12 V and 3.3 V rails. AGP Pro is intended to supplement, but not replace, the existing AGP connector set. There are an additional 20 pins at the start and 28 pins at the end of the normal AGP slot.