Do not get OCZ Ram for the P5B Deluxe. I was one of the unfortunate ones who purchased a 2GB pair when it was on sale, just to find out that they don't like the P5B. I called both companies, neither gave me a good answer so I RMA'd them and bought 2 x 1GB pair of Corsair.
I have not heard of any other problems with Ram for the P5B, however, to be sure you can check the Asus forums and look what people are saying about the P5B... thats how I found that it didn't like the OCZ.
I've read people have good luck with Patriot. Corsair has been hit-or-miss on the PC6400's with the P5B's. If you go Corsair, pay a little extra and get the Cas 4's. They seem to be fine. Stay away from the Cas 5's or you might have to RMA them a couple times. Just what I've found...
The Asus P5B is a pretty good board all around. The problem was that it automatically couldn't adjust the ram voltage for some ram types. This meant that some RAM brands were simply not a plug and play affair, but certainly didn't mean that they didn't work.
If you have an Asus P5B and some RAM that doesn't work, check out the RAM voltage specifications. You'll probably note that the ram requires over 1.8v, and by default, the P5B deluxe motherboards attempt to run ALL ram at 1.8v.
I found the best way to sort this problem out, was to insert one stick of 2.15v RAM into my motherboard, still running it at 1.8v. You should be able to make it into BIOS with out the system crashing. Then, up the RAM voltage to the RAM specifications. Save, and shut down your PC. Add all the sticks of RAM, double check all is well in the BIOS, then boot your OS.