Intel BOXD850MVSE Quick Reference Manual page 15

Install RIMMs into bank 0 first. If the desired memory configuration has been
achieved, insert CRIMMs into bank 1.
If memory is to be installed in bank 1, the RIMM modules to be installed must
be identical in size and density to each other, and match the speed of the RIMM
modules in bank 0. For example, if bank 0 has two 128 MB RIMMs of
PC800 RDRAM, bank 1 would require PC800 RDRAM also, however, any
other supported RIMM modules such as 64 MB or 128 MB could be used.
0
1
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