Very interesting!
 
How do you actually enable windows caching in Sonar's preference?

tlw
Spooling to disk while bypassing the Windows cache at one time also resulted in faster and smoother sequential reads/writes of large files such as multi-track audio.

While this would be true for a single track, won't multi-track audio's tracks each go to different files (which may be far apart if you're unlucky) ?  At least having a dedicated audio drive keeps the head movement restricted to handling only the tracks and not have it also move around for OS and other program activity.

Dyonight
Good explanation thanks!
 
When you talk of "disk cache" I understand physical faster memory on the actual drive. Is there a way to virtually boost this hardware cache with a ramdisk or something? Is it worth it?

 
There is some memory on the physical drive for caching, but the OS uses a lot more memory for its own disk caching. I did a test once when my system still had 8GB RAM, and the OS used 1GB of that for disk caching.
 
To be honest, I don't think there is much you can do these days to improve disk caching since OS disk caching has been fine tuned and has become very sophisticated and effective. Any 3rd party utility claiming to improve disk performance will probably do more harm than good.
 

I also haven't used a RAM disk since my Atari days with Dr. T's KCS. However, I've been turning on my new Haswell on a MSI mobo. I have 16GB RAM and haven't seen anything use more than 10 GB, so far. I'd just started looking at the MSI overclock tools and noticed the RD. I've also got a 2 SSDs (boot and BU) with most stuff on the HDD's. I set the RD up and things sure seem to work faster and better. My main motivation was to remove all the junk that the system uses for temp files off the SSD which was plenty fast, but this is much better so far and the OS seems much more responsive. More so than I expected, which is why I thought to post. This seems even better than OC from 3.3 GHz to 3.8 GHz. I'm not likely to use the overclocking but wanted to set it up and learn it now rather than later.
 
While I'd like to try this with my laptop, the OS needs all of the 4GB's it has, so that won't work. But with excess idle memory floating around on the desktop, I figured I'd put it to use. 
 
Even if Sonar doesn't directly use the 'sys temp' directory (which automagically gets pointed at the RD, along with the various browser caches by MSI), OS support and particularly graphics seem much more smooth. I've also noticed that my VRAM on the graphics cards doesn't get used as much either, but that's a game thing. 
 
I'm aware of the downside of RD's, so won't be 'storing' anything on it (other than very temporarily anyway). I already disabled the 'Hibernate' feature and finally got sleep working OK instead. A RAM sized (16GB) hyberfile on my SSD (120) GB is not desirable as it is still just basically a temp working state. Waking from sleep is faster and doesn't use much more power than Hibernate. Of course, I don't disable Hibernate on my laptop, but it doesn't have an SSD and don't much use it on batteries.
 
Good comments above about pagefiles and RD's. If one uses the RD correctly, pagefile use should be reduced, though the pagefile should be on a SSD or HDD and only accessed by the OS when it needs more address space. Pagefiles don't belong on RD's. 
 
While a bit OT for Sonar users, I try to keep things stable across all the constant updates and wondered if others may have tried this. Sonar is one of my more quirky installs and I wouldn't want it to have issues I've created. I'm still pretty bummed about the browser not showing compressed files. 
 
I haven't really exercised Cambridge too much yet, but will probably try some memory intensive stuff.
 
 
 
 
 

Well thanks to all for the background info. 
However, I'd been hoping that somebody might have already done some A/B comparisons and could share their actual experience. Mostly, I was wondering about unintended consequences.
 
I'm pretty familiar with 'caches', tracks, HDD access times (I designed HDD H/M, etc for more than 20 years).