[SOLVED]

EDIT: PROBLEM SOLVED.
 

Hey DreamForecast . . . welcome to the forum !
What soundcard do you have ? And what are you ASIO or WDM buffer settings ? (in preferences)

Could it be how your have the plug-ins configured? Some plug-ins can stream samples to reduce RAM usage. They can be reconfigured to load completely into RAM.

The plug-ins are where this config would happen. SONAR does not limit the RAM a plug-in uses.

daveny5
I don't believe plug-ins necessarily chew up that much RAM. Windows could be swapping some of that into the paging file. Audio tracks do take up a lot of RAM. I don't think that's what's causing the pops and clicks though. What do you have your ASIO buffer size set to? What bit depth and sample rate are you using? Maybe you should try turning off the Windows paging file and see if that makes it use more RAM. 

It doesn't actually pop/click too much during playback.  Audio works fine.  It's just the soft-synths.  It's when I'm playing a heavy instrument live (after many heavy instruments have already been added -- usually 25-30 tracks).  I should also mention my latency, usually super low, starts to lag more and more.  My buffer size is currently set to 256 (both in Sonar and in my ASIO panel).  I'm running at 48 kHz / 24 bit. 
 
I'll try the Windows paging file thing sometime.  How bad is it really for your system?  I've read mixed opinions on that.
 
Thanks for your response.

daveny5
I don't believe plug-ins necessarily chew up that much RAM. Windows could be swapping some of that into the paging file. Audio tracks do take up a lot of RAM. I don't think that's what's causing the pops and clicks though. What do you have your ASIO buffer size set to? What bit depth and sample rate are you using? Maybe you should try turning off the Windows paging file and see if that makes it use more RAM. 

Okay, I tried turning off the pagefile, but my problem hasn't gone away.  Sonar still hits the ceiling at about 1.5 GB of RAM.  
 
Thank you so much for your time and effort, by the way, I really appreciate it.

When the project gets a bit heavy I usually freeze the synths I am not practicing or recording to free up  resources.
 
Also if you have added and audio effects that reply on pdc that can cause issues as well.
 
I don't think what you are experiencing is the result of memory but more likely processor.

Hi and welcome here.
 
Have you thought just about a test project were  to plug in  synths and fxs which are
heavy CPU ressource hungry ? One after the other till your machine dies?
I would be curious about your result!
I want to do that with my new machine the next days..
Have fun 
Pragi

Usually to fix the recently described issues would be to adjust interface buffers or freeze tracks. If there are a lot of plug-ins there is an adjustment that can be made to the AUD.INI described here that might make a different.

DreamForecast
 I open up Task Manager to see how much RAM is being used, and by golly, only around 1.5 GB of RAM.  My plug-ins (which are also 64-bit, by the way), are begging to have more RAM but perhaps Sonar X2, the host, is refusing it.  
 

It seems there may be two issues here that may not be related. One is that you are having clicks and pops (presumably from dropouts) and the other is that you do not believe working random access memory is being assigned to Sonar and the various plugins appropriately.

How did you determine that your plugins are begging for memory?

DreamForecast

slartabartfast
It seems there may be two issues here that may not be related. One is that you are having clicks and pops (presumably from dropouts) and the other is that you do not believe working random access memory is being assigned to Sonar and the various plugins appropriately.

How did you determine that your plugins are begging for memory?

1. I think you may be right.  However, despite the pops and clicks, I am not getting dropouts, which is weird.
2. I think the plug-ins need memory because
- they keep killing notes when I play too much (though those are fully polyphonic synths).  Also, there is a crackle sometimes when I play them. 
- a latency delay starts to develop (now I'm not sure if this is related to RAM or Sonar or soundcard -- sorry for being such a noob and thanks for putting up with it xD)
 
Yeah...

As Tom stated above it doesn't sound like your issue is specifically ram related. I would suggest that you load up a East West Quantum Leap synth or two in a new project and I'm guessing you will see an increase in ram usage. I believe your issue is related to configuration of audio and midi buffers. But there are already people here who can walk you through that better than I.

You should be able to tell if it's processor related or not by looking at the CPU usage meter on the control panel. As soon as one or more of the cores start peaking into the red, you're going to get pops and clicks. 
 
The latency delay could be related to plugins that use "look ahead" technology, for instance the Concrete Limiter. I would try turning off your effects one by one to determine if any particular ones are causing the latency. 

Do re-enable the pagefile for the OS disk only, as system managed. It is needed for windows to do what all it does. Including recording data about errors.