I was totally baffled by the problem until I ran an xperf trace in the Windows Performance Toolkit and saw that the spike was being generated from ndis.sys and tcpip.sys. I use the PC for audio production amongst other things so this causes me big issues. Every few mins on the PC I would experience a DPC latency spike of around 95000us to 100000us which would occur right when the audio dropouts, mouse freezes, and probably network pauses would occur. I had also been noticing that my network performance had been pretty poor intermittently on this machine for a while, occasionally experiencing dropouts and low download speeds (yes I know that can be caused by many other factors but please hear me out). Nothing made any noticable difference at all. Turn on all offloading settings on Ethernet NICĭisabling Network Location Awareness in Windows Update BIOS and all drivers to latest versionsĭisable CPU and PCI Power Management in BIOSĭisabled onboard Sound (I use a separate professional audio sound card), Wifi, BluetoothĬhange power management settings to High Performance and Disabled USB selective suspend In troubleshooting the issue I tried everything I could think of such as:

I'm running Windows 8 Pro 64-bit and am using the latest Intel driver for the controller (12.6.45.0). It appears that the Intel 82579LM based Network Controller driver may not be correctly optimised for Windows 8.

After weeks of troubleshooting DPC latency problems on my Lenovo Thinkpad T420 laptop which were causing audio dropouts and mouse freezes every few mins I have finally tracked down the source of the issue.

Intel centrino wireless n 1030 freebsd