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High DPC Latency + BSOD after installing new drivers

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#1 Zmaz


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  • Local time:02:48 AM

Posted 30 March 2012 - 05:02 PM

I installed a bunch of new drivers via the System Update tool on my Lenovo Thinkpad T520, and after have had a number of problems. My system as a whole ran much slower, and I did some poking around in Task Manager, Process Explorer, and LatencyMon. LatencyMon shows that ntoskrnl.exe and hal.dll have a high ISR count, and ndis.sys, tcpip.sys, netbt.sys, nvlddmkm.sys, and iaStor.sys all have a highest DPC execution time above 1 ms. ntoskrnl.exe, iaStor.sys, nvlddmkm.sys, HDAudBus.sys, SynTP.sys, DzHDD64.sys, and ndis.sys all have high DPC counts (significantly greater than the other drivers and processes running during the time I monitored). In Process Explorer, firefox.exe, svchost.exe (containing the Base Filtering Engine, Diagnostic Policy Service, and Windows Firewall), and SynTPEnh.exe all have high numbers of page faults. Also, SimpleTap.exe is using over 100 MB of RAM, which seemed strange, and the svchost.exe containing, among other things, a bunch of stuff related to my wireless connection, also is using over 100 MB -- I'm not sure if that's normal or not.

I've had a few BSOD's since updating the drivers. BlueScreenView says that the Bug Check String for all of them is DRIVER_VERIFIER_DETECTED_VIOLATION. The files highlighted in red are ntoskrnl.exe and WinFlash64.sys for one of them, cpudrv64.sys and ntoskrnl.exe for another one of them, and ks.sys, ntoskrnl.exe, and STREAM.sys for the most recent BSOD. Also, since updating the drivers my system runs hotter, and battery life has decreased by more than half.

I've tried doing a clean boot with no success, and I've also tried disabling things in Device Manager. The only thing that seemed to make an impact was disabling my wireless adapter (Intel WiFi Link 1000 BGN), but even after doing so my system was slow and I still had fairly high (though lower than before) DPC latency. I uninstalled the driver for my wireless adapter and installed an older one (though I'm not sure if it was the one I had originally, before updating) but it made no difference.

I'm happy to try anything, run diagnostic tools, upload dumps or traces, etc.; I'm really frustrated with trying to fix this, and would like to get to the bottom of it.

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