Unknown DPC latency source... Q9200?

Hi guys,

I've been investigating this issue with DPC latency causing audio pops and stutters for a while now. Large spikes were attributed to the GPU clock transitions and were easily reproducible and I think have now been solved with the 257.15 drivers.

However I have also been fighting spikes of unknown origin that seem to happen randomly. I have not been able to reproduce those in any way, although they seem to be happening more often when heavy multitasking is done. Here's what the DPC checker looks like when they happen:



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I've run the tracing tool that Stamatisx posted in the Alienware forums, and he took a look at it and cant figure it out. The DPC comes from an "unknown" process which we cant identify.

I was wondering whether this could be a problem related to my ES Q9200 chip. If other people using an ES chip experience similar problems it would be useful to know... same thing if you're using a retail chip and get those spikes. I used to have a P9700 chip but I dont remember if I had these weird spikes before. Any ideas?

 

I doubt it's the Q9200, I can tell you that.

What graphics driver are you using and what are you doing when it spikes?

 

it does that with all drivers... now using the 257.15. I was really hoping the new driver would solve the problem but it doesnt.

man i wish i could answer that question... it seems completely random. maybe i should make a logbook or something and write down a note each time it happens to see if i can identify a pattern. as I said before I have run the tracing program and Stamatisx had a close look at it and he was clueless... if it was a particular program or task we would know.

 

I just ran a test:

Listen to ESPNRadio via Firefox, music via WMP:



This was constant, until I closed the window. Then the latency immediately went green/yellow. Once I started WMP or internet radio up again, the constant 15k spikes immediately returned.

So, then I uninstalled my Realtek drivers, restarted the computer, and let the default driver install.

Now, playing WMP and internet radio for over ten minutes:



Hmmmm... ?

 

I have the same configuration and i'm gonna test when the official driver is out.

 

Since uninstalling the Realtek, I'm still running in the green, a bit of yellow.



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The only time it spiked red was when a game was loading.

 

interesting findings Kevin, thanks for sharing...

I have been using the default windows 7 audio drivers (uninstalled the Realtek ones ealier this week) and still experiencing DPC problems once in a while.

I've been keeping a log of my DPC issues. Since thursday night it happened 5 times, 3 times while playing WoW and listening to local audio files with itunes (no streaming) and 2 times when working with Matlab (no audio or video playback at all).

http://i49.tinypic.com/23046g.jpg

The latency is not consistent or reproducible when playing WoW... I can play for 2 hours straight without any problem and then suddenly it will start stuttering for no apparent reason. I have a feeling the problem is caused by a hidden task running in the background or something, but I cant identify it.

 

LAN/Wireless/Fingerprint reader?Anything smaller?

 

I am also having the Dpc spikes and get video/audio sutters with windows7, but when I have vista installed spikes are less. Can anyone explaon what happening?

 

Hi Rambo29, I do get yellow spikes every 10 seconds from my wireless adapter, but I dont think these huge spikes are related to it.