At the current IDF surfaced some new details concerning Intel’s idea of RDRAM’s future in Pentium 4 based systems. It turned out that despite Intel’s launching of a DDR SDRAM for Pentium 4 in early next year, the company doesn’t want to give up using RDRAM. According to Intel, Rambus memory in Pentium 4 systems will be developing in two ways:

1. In High-End systems Intel is intending to transfer its CPUs to 533MHz quad-pumped bus next year, so these systems will use dual-channel RDRAM working at 1,066MHz instead of 800MHz it currently supports.
2. Besides that, Intel is going to start using four-bank RDRAM developed by Samsung in mainstream desktop systems.

Samsung officials said the four-bank RDRAM chip will have equal or better performance than the current 32-bank Direct Rambus DRAM. A major cost savings results from less space on the die required to control four banks as 32 banks on the current chip. The four-memory-bank chip can cut the Direct RDRAM cost by 20% to come close to parity with SDRAM in full production. The corresponding chipset supporting single- and dual-channel four-bank memory is scheduled for launching in early 2002.
As a result, it turns out that with a new Brookdale chipset Intel will simply try to calm down some Rambus-haters, since they will have an alternative choice of PC133 SDRAM and DDR SDRAM. However, NetBurst architecture of Pentium 4 requires very high memory bus bandwidth, which cannot now be obtained with DDR SDRAM even (especially taking into account the way it will be implemented in Brookdale). Therefore we do understand Intel, which is to introduce 1,066MHz RDRAM. This memory will provide 4.2GB/sec bandwidth and will be just what the doctor ordered in High-End servers and workstation.
As for the four-bank RDRAM, this memory has every chance to become another alternative to PC133 SDRAM and DDR SDRAM in Pentium 4 based systems, if the cost of this new memory will be comparable with that of SDRAM. And then the market will decided which one of these deserves being called the best.
You may find more details on the matter at CNet and EBN.