I've finally found the causes(!) of the latency spikes.
The first one obviously was the WLAN card. With that disabled I still had 15 seconds spikes and a few random spikes and no internet. Then I disabled the Microsoft ACPI-compliant Control Method Battery and that took care of the 15 second spikes. Now I still had a few random high spikes and no internet and no information about my battery life. Then I switched from my HD5470 to my Intel Media accelerator and now FINALLY all latency spikes are gone.
But now there's no internet, no battery information, no highpeformance quality graphics.
Would you still recommend to contact microsoft support? What does PSS mean?
About the WLAN: I tried using only my other NIC with an ethernet cable, but that still gave me DPC latency spikes. So I uninstalled Norton Internet Security and now I can browse the web, download and upload using my other NIC card without latency spikes. If I use my WLAN card, I still get a number of spikes just after downloading or uploading, similar to the images I posted earlier. Very weird:
Norton uninstalled and only the WLAN card causing DPC latency spikes just after internet usage:
This post has been edited by VultureX: 08 April 2010 - 08:27 AM