DPC Latancy

[SDRrookie]

Hello,
I built up a new system that that is working fine with one exception. Some thing is causing DPC latency spikes up to 5ms. Background DPC is running 15us.

How do I go about looking for the cause?

MB ASUS M4A87 Pro
AMD Phenom II 4x 3.2 GHz 955 Black Ed

OS: Win XP SP3 PRO

Thanks,

 

[Outlander_04]

can you notice a 5 ms latency?

is it a problem ? if so why

 

[SDRrookie]

The application is an SDR ( software defined radio ) so the data from the radio to the PC is very much like streaming audio. Any gaps in the buffers will cause pops in the audio or worse, errors in the DSP functions.

There are reasons for using small buffers, which make latency even more of an issue. I'm looking for suggestions on how to identify what piece of hardware is causing the latency. The next step being, can anything be done about it.

I have noticed that some options on the graphics card increase the background latency. I'll try taking the graphics card out and see what that does.

Rgds,