Do I need more than 4GB of RAM in Exchange servers?

In response to a recent post about the /3GB switch and an inquiry from my project leader, Clayton, I thought this would be a good blog topic.

Do you need more than 4GB of RAM in your Exchange servers? No, no, no, no. Never. (Well, in no Exchange situation that I can think of). The Exchange STORE.EXE is the biggest use of physical memory, but I have never seen it allocate more than 2GB of RAM. The system attendant (MAD.EXE) and IIS (INETSRV.EXE) both like lots of RAM, but I have never seen this allocate more than a few hundred MB. So, there is never a reason for more than 4GB of physical RAM in an Exchange server.

Save your money. Buy my book or something instead. Or just send cash! :-) (I'm kidding here for those of you that take everything so seriously!)