HWInfo causing DPC latency with AW17


New Member
Hi there,

I've been using HWInfo64 for a while now and I have been getting DPC latencies in the form of crackling and popping on my Alienware 17 (2013 Model) with an i7-4700MQ. As soon as I close the program the DPC latencies are gone.

I do have EC support unchecked and I have HWInfo read the EC sensor in order to allow me to control the CPU and GPU fans separately. I am not sure if there's a way to let me control the fans separately while having no DPC latencies.

EDIT: disabling SW SMI removes fan access. enabling EC support removes my ability to control the CPU and GPU fans separately.
I'm afraid, there's no perfect solution for this. You should be able to significantly reduce the latency by disabling the DELL EC sensor in the sensor window. It's not required to have this sensor enabled for fan control unless you want to use its values as temperature source for fan control (you can choose different temperatures as the source). You will then probably still see a few spikes in latency when HWiNFO changes the fan speed, but there's nothing more I can do about this - it's implemented that way in the firmware.
Oh ok, so the high DPC latency is just a side affect of HWinfo? I did try disabling the EC sensor is the monitoring section but the after a minute the latency returned. the popping and crackling is, at best a nuisance and at worst an annoyance.
The high DPC latency is caused by any access to the DELL EC sensor (either reading current sensor values, or settings a new fan speed). This is a specific issue of this kind of sensor (and a few others).
Have you disabled the entire DELL EC sensor (the heading) as well ? If yes, how frequent are the DPC latency spikes then?
OK, do you have any suggestions on other settings that i could disable to test?

i have disabled the EC monitoring (it means i don't get the fan RPM but oh well) to see if it does reduce the frequency of the DPC latency spikes.
I have AW17 R2, and in the new version of v5.04-2630, when enabled these options: Low-level PCI Access, TPM Check, EC Support and other default options. I didn't hear any sound crackling and popping anymore. Except run DPC Latency, I still can see sometimes it poses over 4000 us, but it's not really effect the sound system.

Thanks to Martin for his new version :)