Bit summed it up pretty well.
 
In short, if you're working at ultra low latency (running heavy loads), low/consistent DPC latency is critical.
The further your needs are from this extreme, the less important DPC latency becomes.
A well configured current generation desktop can yield DPC latency that averages 2-8 uSec with an occasional peak in the 20s.
That's what you want for the best possible low latency audio performance.

If you're looking to solve a high dpc latency issue, it's worth downloading LatencyMon from http://www.resplendence.com/main. It not only monitors the latency but also lets you identify which particular processes/drivers are causing the problem, especially if you get big red spikes even with any wireless network adaptors disabled in device manager.

It sometimes seems to miss spikes that the dpc latency checker spots, but even so it can save a great deal of time compared to identifying the culprit process(es) by trial and error.

tlw


If you're looking to solve a high dpc latency issue, it's worth downloading LatencyMon from http://www.resplendence.com/main. It not only monitors the latency but also lets you identify which particular processes/drivers are causing the problem, especially if you get big red spikes even with any wireless network adaptors disabled in device manager.

It sometimes seems to miss spikes that the dpc latency checker spots, but even so it can save a great deal of time compared to identifying the culprit process(es) by trial and error.

ah.. i was assuming thats the one Synk was using..............but mebbe not (as i read it again), but yup its the better one.

Glad I found this post but I'm still in the dark.
I'm getting appalling latency that's well over the 16000 line.
I wish the latency checker would tell me which devices were the worst (or main offenders) I've tried disabling lots of things but 
still no chance and I'm getting awful clicks and pops that are making sonar almost unusable right now.
Are there any better programs that DPC Latency Checker that give more info as to what is causing the problem?

Steve 

For me 300 is the absolute maximum .....the rest is not considered as optimized for audio but workable ..

Lappy :

Sony VGN BX 197 : 4 us !!  XP
HP 8710w : 35 us  XP
HP 8540w : -75-180  Win 7
HP 8560w : 90-180...Win 7 

MBP 17 (not kept) : 130-170 us win7

Desktop : 120us ... Win 7

That sony i sued to call it my "swiss horlogery" !!

Well, I noticed something interesting.  I use a TASCAM US-1800 as my audio device with ASIO 64-bit drivers.  My average is about .2ms and .32ms peak (sorry, I speak in milliseconds, not micro).  I'm using the sample "Jodi Good - Where did we go wrong" sample track as a test since it has a fair amount of plug-ins and effects.  When I go to Preferences -> Audio -> Driver Settings -> ASIO Panel and set my TASCAM Audio performance to "lowest latency", SONARPDR.exe will crash every time.  When I kill the SONARPDR process and restart, sometimes Sonar X2 restarts and sometimes it doesn't.  If it does start, then I get no audio at all.  Requires a system reboot.  BTW, I am running the latest patch, where in one crash, it opened the debug dialog box allowing me to send it off to Cakewalk support.  There are far too many factors that can cause high latency and will vary from machine to machine.  My rule of thumb is turn of at very minimum anti-virus and real-time disk defragmentation and see what you get.   Thanks tlw for the link to LatencyMon.  I'm going to try that and see if I can narrow it a bit. I'm finding in my Sync and Caching settings that the Record Latency Adjustment (samples) is showing my PCIe card that I use for live video streaming (Decklink by Black Magic Design). If I try to change it the use the TASCAM US-1800, it won't hold the setting.  Will have to call Cakewalk support on that one. It's not checked off in the Preferences -> Audio -> Devices section either.

twaddle:
 
Try LatencyMon - see my post above.

harpman58


Well, I noticed something interesting.  I use a TASCAM US-1800 as my audio device with ASIO 64-bit drivers.  My average is about .2ms and .32ms peak (sorry, I speak in milliseconds, not micro).  I'm using the sample "Jodi Good - Where did we go wrong" sample track as a test since it has a fair amount of plug-ins and effects.  When I go to Preferences -> Audio -> Driver Settings -> ASIO Panel and set my TASCAM Audio performance to "lowest latency", SONARPDR.exe will crash every time.  When I kill the SONARPDR process and restart, sometimes Sonar X2 restarts and sometimes it doesn't.  If it does start, then I get no audio at all.  Requires a system reboot.  BTW, I am running the latest patch, where in one crash, it opened the debug dialog box allowing me to send it off to Cakewalk support.  There are far too many factors that can cause high latency and will vary from machine to machine.  My rule of thumb is turn of at very minimum anti-virus and real-time disk defragmentation and see what you get.   Thanks tlw for the link to LatencyMon.  I'm going to try that and see if I can narrow it a bit. I'm finding in my Sync and Caching settings that the Record Latency Adjustment (samples) is showing my PCIe card that I use for live video streaming (Decklink by Black Magic Design). If I try to change it the use the TASCAM US-1800, it won't hold the setting.  Will have to call Cakewalk support on that one. It's not checked off in the Preferences -> Audio -> Devices section either.

Harpman , this is a driver lock when you need to reboot ...when sonar crashes ...it sometime kinda lock your drivers and need a reboot ..

Jim Roseberry


Bit summed it up pretty well.
 
In short, if you're working at ultra low latency (running heavy loads), low/consistent DPC latency is critical.
The further your needs are from this extreme, the less important DPC latency becomes.
A well configured current generation desktop can yield DPC latency that averages 2-8 uSec with an occasional peak in the 20s.
That's what you want for the best possible low latency audio performance.

Wow,I was under the [mistaken,now I see]impression that W7 x64 introduced,a whole bunch of things that made the super low latency that YOU speak of,as a thing of the past,also isn't it kind of a bad idea,to turn OFF,the High Precision Event Timer?[HPET],as I seem to remember someone saying it[HPET] can be important,for audio related tasks?


An average of 2-8 us!!!,with a peak "occasionally" in the "20's"!!!,incredible low DPC,that is,and pretty un attainable for normal humans. 
RK

Thanks for the link for the other checker tlw.

Jim, wow, I'll have to do some digging then, to get that low anyway. Generally speaking, before I decided to use the DPC latency checker, my DAW has been fine and I've had over twenty different soft synths all running at the same time, which includes Absynth with some CPU hungry granular effects. I was only using the checker out of curiosity really.

Since I got this laptop I meant to go for dual boot of W7 and have one for my general office and web browsing tasks and the other for a cut down OS for my DAW. I just haven't got around to it yet. It's how I used to run my XP desktop and it worked quite well.