HD Recievers & Access Cards

[Skybum]

How can I find out which cards work in which HD recievers. I see that some will only work with p4's. But knowing which ones I can then buy my new reciever with the right info. I am upgrading my dish to a 3 lnb and would like to watch HDTV shows and NASA.
Please respond with any info you may have.
Thanks

[NEVADA1]

You Will A 5 Lnb Dish And A Direct H20 Or A Hr20 To Get The Hd Programs In Sept...........