The memory controllers in up-to-date chipsets have some limitations (volume/memory speed ) . For example, for the fastest memory operation modes there is some limitation according to the number of occupied DIMM slots .
As reports associate with the reference to Hynix , nehalem processors memory controller will also have some limitations on high-speed modes and large capacity memory . For example, it will be possible to use all three channels only with DDR 3-1066 memory module . For the passage to DDR 3-1333 the number of DIMM modules will be reduced to two pieces (for each channel). It is completely regular: faster memory, result in less DIMM slots quantity ( used ) . At least, the current generation of engineering models provides similar limitations.
However, the owners of desktop systems on base of nehalem processors will not even notice such limitations. First, nine DIMM slots will be hardly present on desktop motherboard . Second, even with two slots in each channel the memory capacity will be decent, and three-channel mode will be preserved.
Servers system on base of nehalem processors can use memory module with metaRAM technology support : Special chip witch can increase the number of used memory by two or four times.