MEMB#0 and MEMB#1 installed DIMM's : Type:2B; Size:2 GB;
MEMB#2 and MEMB#3 installed DIMM's : Type:2A; Size:2 GB;
It's look like 1-RANK and 2-RANK DIMMS.
Notes about memory configuration:
1-Rank and 2-Rank DIMMs cannot be mixed in the same memory group.
So you need reinstall DIMM for have same type of DIMM at one memory group.
For example, install Type 2A at bank A on all MEMB and Type 2B at bank B.
( All DIMMS at one bank should have same P/N )