Testing on an idle desktop, why would the parallel plan take longer in another run

GokhanVarol 2013-06-07 00:09:19

The CXPacket waits are longer in one run compared to the other. But why would it be, this is my desktop doing nothing but testing at the moment. Why would same step duration would be high at one point and low at another point. It's my local desktop, it's running nothing else (I have outlook open and lync and webbrowser but during testing I do nothing with sql server, it has xeon I7 3.6Ghz with 4 core and 8 with hyperthreading).
What should I be looking up for to troubleshoot?
Thank you

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