Recently I invested in a couple of 1 GB RAM sticks for my CRM SBE server, giving me a total of 3 GB. I felt I got some benefit from it, but not as much as I had figured. Then more recently I happened to be trying to relieve some memory use on the server so I could run a test VPC briefly. I noticed that I had 4 SQL server instances running. This is as expected with the default instance which CRM uses, SharePoint, SBS Monitoring, and ISA 2004. One of these I noticed was using 1.2 GB! Must be my CRM. Since I didn't need CRM while I was running my VPC, I stopped that instance of SQL. Nope! The 1.2 GB was still there. Well, must be SharePoint. Stopped it. Nope. Tried SBS Monitoring. The pesky 1.2 GB SQL process just continued to stare me in the face! Finally I stopped the ISA instance, MSFW. Wham! the 1.2 GB was released. I was astonished. So, I brought up SQL Enterprise Manager, right-clicked on <server>\MSFW and selected Properties. From the SQL Server Properties dialog box, I selected Memory. There I found that the MSFW instance had no restraint on memory useage, the default. I then selected the Dynamically configure SQL server memory and slid the slider back to around 260 MB. That may still be too much but I don't know how much is really appropriate. But it's a lot less than 1.2 GB! So now I'm happy.
Well, I thought I was until the other day I happened to check on the RAM for my default instance of SQL which CRM uses. I figured it was set to dynamically use all the RAM it could get. Not so. I found it was set to some relatively small value somewhere in the 250 MB range. Ouch. I slid the slider back up to allow it to use up to 2 GB. Afterall, that's why I bought the extra RAM.
So, maybe when you have nothing better to do and you're tinkering around your server, you just might want to check on how your SQL server instances are using memory. It might surprise you.