High DPC Latency spikes in DV7-7000 series

Hi all:

I wanted to know if anyone with the new DV7 or DV6 7000 series, Ivy Bridge, laptops were getting regular spikes of DPC (Deferred Procedure Call) latency. DPC latency is critical to keep low for certain tasks, like video playback, audio playback, and specifically audio recording.

In order to determine if you have a DPC Latency issue, you can download the DPC Latency Checker here, at DPC Latency Checker.

In order to determine which process is causing the highest DPC latency spikes, you can use Latency Monitor here at Resplendence Software - LatencyMon: suitability checker for real-time audio and other tasks.

How high is your DPC latency spiking? What is the responsible process?

I'm getting regularly into the 2000-3000 microsecond range, and the cause is ACPI.sys.

I hope you can respond with this information so I can gather the data and approach HP about the problem.

Thank you for your help!

 

I too am concerned about this issue as I have just ordered a DV6T-7000 for some gaming but mostly audio recording. I will be sure to report latency settings when mine comes in, which is about May 28th.

Have you tried reinstalling 7 with a minimal non-OEM installation and getting the drivers one by one yourself?

What happens to your latency when you turn off wireless, disable the internal soundcard (I assume you use an external one), and set Processor Scheduling to Background Services?

Have you actually experienced brief audio dropouts during recording at the same time as the DPC latency spikes?

EDIT: Right now, on my old HP 6930p, I get 1000 microsecond spikes every 10 seconds or so, but when I actually view network connections and right click wireless network connection and disable it, I do not get any spikes whatsoever and remain around 100 microseconds the entire time. Simply pressing the wireless button on the laptop to turn it off still results in spikes, but actually going into network settings and manually disabling it does.

 

Hi, my DPC Latency is really good now (almost always under 100 with no spikes) but I need someone to help me determine exactly what caused it to get that low. Here's everything I did (in order):

1. Minimized Image Recovery
2. Made sure Origin wasn't running (only thing I installed so far) and made sure nothing was downloading, including windows update
3. Set Processor Sheduling to "Background Services"
4. Disabled UAC
5. Disabled wireless (just used the button)
6. *important* Went into Task Manager and terminated every non-essential process. This made made my DPC latency under 100 for the most part. However, there were still huge spikes in the red every 15 seconds.
7. *really important* Went into Device Manager and disabled "Microsoft ACPI-Compliant Control Method Battery. This is what ultimately stopped the spikes every 15 seconds. However now you can't see how much battery you have left.

I also found that enabling the wireless after all of this keeps the DPC latency consistently around 180, and disabling it brings it under 100 again.

The problem is if I do everything above besides terminating processes in task manager, the DPC is consistently in the red/yellow. I tried disabling them one by one, but there seems to be a delay between when the "problem process" is terminated and when the DPC latency drops under 100 so I'm having a hard time figuring out which one it is. Can someone help me with this?