Hello Alpesh,
Looking at the data sheets for the 7835 and 7845, there is more of a difference than just requiring more RAM as all of the 7845s are Dual Intel processor MCS.
I couldn't find an exact match for the 7835 I3-K9-CMD2. The closest I could find is the CMD1 specced with a single Intel 5504 at 2.0 Ghz with 4 GB of RAM along with 2x146 GB drives.
The Application server requirements does list a 7835-I3-RC1 with the same specs (Single 5504 @ 2.0 GHz with 4GB of RAM and 2x146 GB drives), with the note that it cannot support multinode deployments.
Based on this, it looks like the difference is just the product ID as the CMD model appears to be the orderable ID for Communications Manager instead of MeetingPlace. Does the customer want to implement a multinode topology or are they looking to move to a single 8.5 audio-only deployment?
Thanks,
Derek Johnson
Conferencing TAC