It may be listed in one of the posts of this long thread, but if you don't mind, please list the exact version of Windows 7 you have installed.
In the above, which was taken from the link I had posted earlier, this is what shows up for me on machines with Windows 7 Professional or Windows 7 Ultimate, except since I am not using a laptop I don't see the Battery option. The red box does not properly encapsulate all the settings under Processor Power Management, but in the image you can see the Minimum Processor State and Maximum Processor State. I have literally set the Minimum Processor State to 100% on over 50 computers I have built in the last couple of years that are running either Windows 7 Professional or more often Windows 7 Ultimate.
Perhaps that option does not appear for some versions of Windows - I do not have any machines running any of the other versions of Windows 7 to be able to check that. My earlier thought when you indicated that "it wasn't there" or whatever the exact phrase was, was read by me to mean you hadn't seen it in the article from the link, rather than not seeing it in the power management options.
Meaning from typed words is sometimes misconstrued, and I try to be careful to avoid that - but don't always avoid it. That was why I had posted the text from the article, with that part in bold. I also had provided the further explanation because that setting most definitely does apply to desktops, and I have personally made that setting adjustment many many times.
I do truly wish you the best at getting things sorted out. It got frustrating at your end, and at mine, during the lengthy dialog of this thread.
My suggestion at changing the thread title was due to the crashes being system-specific problems not caused by Sonar, and to a degree I believe much of the odd behavior noted is also part of those system issues.
The truth of the situation is that most everybody else does NOT have the issues you had/have, and nearly everyone follows a much more conventional process of installation.
Your system is different, with some unique challenges not faced by others, but those challenges are not Sonar's fault, hence my suggestion at title change for the thread.
CPU spiking is a small tiny piece of all of what had been determined thus far.
Many times, device drivers and/or background services can cause latency spikes, which produce pops/crackles/dropouts.
There are a couple of freeware programs that can assist with determining whether or not your system can adequately handle the demands of streaming audio applications, such as Sonar.
1. DPC Latency Checker - this can be downloaded from:
http://www.thesycon.de/deu/latency_check.shtml Please note that if you ever move to Windows 8, that at the current time (to the best of my knowledge), due to kernel differences in Windows 8, that it does not accurately report latency times. That problem does NOT occur on Windows 7, and it works fine there. After downloading and running this program (which you can do from another web-connected computer and put on a flash drive or CD to port it to your non-web computer), anyways you would run this program with Sonar NOT running, and let it run for a few minutes. It gives a running reporting on detected latency, and will evaluate your system for being able to handle running programs like Sonar.
2. Latency Mon - this is the second monitoring program, also freeware, and can be downloaded from:
http://www.resplendence.com/latencymon Again, you would download and run this, per its instructions, without Sonar running, and it identifies potential latency problems.
The above are quite valuable, and thankfully free, and should assist in figuring out latency issues that lead to pops/crackles/dropouts.
Bob Bone