Fastest realistic memory speed (RDRAM or DDR)?

It's been a while since I built a system (see sig) and I am not fully up on all the latest possiblities for another SETI cruncher (memory speed is of the essence) - but I am sure some people here will help me.

For starters I am thinking of buying a PIV 2.26 and a board (probably ABIT or ASUS) that can run with fixed PCI/AGP frequency and using good DDR (PC3200 or better) hopefully between 200 - 225MHz. Hoping to reach around 3GHz with good passive cooling - though processor speed is secondary to memory speed (since I intend to run SETI).

Now at about 200MHz with DDR what is the memory throughput? And how does it stack up against an RDRAM system running at whatever is possible with RDRAM (1066 = 133MHz possibly clocked to 1200 = 150MHz)?

Thanks

Yo

Looking at the PC market as a whole, DDR seems the way forward. It's cheaper than RDRAM, and the performance drop from RDRAM to DDR is not great if you're using good quality DDR.

The people to speak to are the SETI crew, if you want to know haw fast the various combinations of CPU/memory crunch....

The data rates of the two make it like comparing apples and oranges. DDR, will transfer large blocks of information all at once. RDRAM will contiually transfer smaller bits of information but much more quickly. The RDRAM is faster but because of the way it transfers data, there is an increase in the chances that bits of information will get dropped. This is the reason Intel will not use RDRAM on their server boards, but will use DDR instead.