As i had briefly reported abt a problem with the AMD AM3 CPU's, that there is a system unstability when more than 1 stick is used per channel. This is for DDR3 -1333MHz. Well, i just found out that Intel too has a huge number of problems with its core i7. Many of u may allrdy know abt them. Well i did not. I found this:

See the errata section. 21 pages of it !!
It did not make much sense to me, but made me realise that AMD was not the only one with problems with the DDR3 memory controller.

Also, the stability issue does not arise with the AM3 CPU's when DDR3-1600MHz memory is used.

These issues would not arise for most of us on the AM3 as not many of us need more than 4GB(2X2GB not 4X1GB) of system memory.