or a hybrid... another spot to check is windows.old. If you never plan on rolling back to your previous windows version, ditch it thru disk cleanup.

Look for things by "Overloud".    It is one of the biggest offenders on my C drive, despite my telling Sonar to install everything on a different drive.      I'm going to track down and root out that stuff if possible. 

Dan,
 
Have you looked into the Seagate SSDHD drives as your main drive.  They are not as fast as SSD, but they are  faster than the traditional HD.
 
4 TB is less than $200.00 and that's a heck of a lot more space than a SD for the same price.  As the SSDHD becomes use to your applications, it opens them faster.  If you are using the SSDHD on your DAW only, then it will be a great investment as it remembers your Daw actions and affiliated plugins and Soft Synths
 
I purchased one and now I am waiting for Windows 10 to became available (no beta's) to install in on my DAW for Sonar Platinum. 
 
Do a search for SSDHD and look at the videos and read the reviews.   Seagate SSDHD 4 TB Drive
 
I hope this helps.

williamcopper
Look for things by "Overloud".    It is one of the biggest offenders on my C drive, despite my telling Sonar to install everything on a different drive.      I'm going to track down and root out that stuff if possible. 

But if you want to use Overloud's REmatrix Solo, which is a pretty cool convolution reverb, don't delete the impulses or it won't do you much good...

Why not move them now and create a shortcut to them? That's what I did with Dan's tutorial on recording drums (very good by the way).

I am not sure of others experiences (and to be fair, i've yet to pull the trigger on an SSD), but all of my trusted IT friends (guys that build systems for themselves and their companies) strongly and solely recommend Samsung SSDs - EVOs and Pros.
 
Not saying a Seagate won't do the trick, but when I pull the trigger it will be for a Samsung.

I recently installed both a Samsung SSD pro, 500 GB and a Seagate SSHD, 3 TB.    The samsung is, as far as I can tell, flawless; I'm not entirely convinced about the seagate, though I've always thought they make good products.     SOMETHING occasionally makes a noticeable lag in doing simple things like accessing a CAL program, but it is quite possibly because I have indexing turned off on my Seagate SSHD disk.   (edit) I also have a Samsung SSD evo, 500 GB, which I was less convinced about, but it could be because I was influenced by marketing messages to spend double the amount for the newer better model.

Another sanity check is to open windows explorer and search the drive for "large" or "gigantic" files by size, and get insight into some things. Many programs also allow setting temporary/cache folders, with audio/video programs being biggest ones to tweak.

Cleaning temp folders regularly is also a good idea as Craig mentioned. So many programs write their temp files to disk and don't clean up after themselves.

In the past, I know Seagate was known for not having the best Hard Drives on the Market.  I stopped using them over 15 years ago. But times have changed and Technology has changed as well.  If I want larger storage capacity with speed, but don't want to pay the outrageous prices for SSD 2 or 3 TB which is going into the thousands, I have to look at other possibilities.   4TB SSDHD at less than $200, and it is faster than a conventional hard drive, heck I will give it a shot. 
 
(JS) ... Just Saying