Click on the Memory tab to bring up the screen shown below.

Click on Properties.  Continued at the top of the column to the right.

It should come up on the General tab.  If you look almost dead center, it lists the total memory on the computer you are using.  Mine says 16265 MB.

Click on OK, exit SQL Server Management Studio and we are done.  Thanks for reading through this and I hope it helps!

Right click on the server you are configuring.

As you can see SQL Server is saying it will take 2147483647 MB if available.  (BTW, if you have that much, you can probably ignore all of this. <G>)  What we would like SQL to have is 90% or whatever is left after giving the OS 2 GB.  So in my case the math is 16 GB * .9 which equals 14,400.  16,000 - 14,400 = 1,600, so I will go with 14,000 and give the OS the 2 GB.  (16 GB is actually a bit more than 16,000 MB, just trying to keep it simple and for this it's close enough. <G>)  

Fill in the authentication info.

If left unchecked, Microsoft SQL Server will take all your available memory until the operating system itself begins using paged memory.  This can result in significant speed degradation.  Use the steps below to cap the memory and avoid this.

Capping SQL Memory

Open SQL Server Management Studio (SSMS) as shown below.