Oh My God
I am also having DPC Latency problem with one of my PC
Check this screenshot
How do I fix this?
Edited:
Only when using YouTube
I can see you use Vista/7 PC, so please install Windows Performance Analysis Toolkit ,run xperf and see results.
With Stack walking method, you can see what function of the driver causes this DPC Latency.
1. Add the following environment variable:
_NT_SYMBOL_PATH = srv*C:\SrvSymbols*http://msdl.microsoft.com/download/symbols
2. From a command prompt, navigate to the Xperf directory and type
xperf -on Latency –stackwalk Profile
3. Wait for the high DPC activity to occur
4. type this and analysis will stop
xperf -d stackwalk.etl
5. Then run this command:
xperf stackwalk.etl
6. After opening xperfview window, go to "Trace" menu and check "Load symbols". If License certification window appear, press "Yes" and wait a minute.
7. Go to the area [DPC CPU Usage] and select high peak, then right click and press [Summary Table] on context menu.
8. Click selector tab (left in window), open [Column Chooser] and check Function at least.
9. You can see what function causes high DPC Latency in "Function" column.
10. Please report your findings here. Drivers' name, function, or any other findings.
Sorry for my bad English, I brought this way from Japanese WDK Support blog and I don't have enough skills to translate whole article.
Best wishes