The easiest way to test some stuff is to make a new hardware profile.
Control panel System > Hardware > Hardware profiles
Copy your current profile and rename it to something like "Audio"
Restart pc and boot in to the new "audio" profile.
Go to Control panel System > Hardware > Device manager
Disable your internet wlan ethernet webcam and anything else you don't need. BE CAREFUL!
http://www.thesycon.de/deu/latency_check.shtml
DL the latency checker and run it in both profiles and notice the difference in latency.
In my audio profile with the dux xp I make simple batch files to start and stop services that aren't needed when recording.
Make sure "hide extenstions for known file types" is UNTICKED in : My computer > Tools > Folder options
Create a new .txt and paste the following :
net stop "Dhcp"
net stop "TrkWks"
net stop "Dnscache"
net stop "Netman"
net stop "Nla"
net stop "lanmanserver"
net stop "SSDPSRV"
net stop "LmHosts"
net stop "TermService"
net stop "SharedAccess"
net stop "stisvc"
net stop "lanmanworkstation"
Save the file and rename it to "stopnet.bat"
Make another new .txt and paste the following :
net start "Dhcp"
net start "TrkWks"
net start "Dnscache"
net start "Netman"
net start "Nla"
net start "lanmanserver"
net start "SSDPSRV"
net start "LmHosts"
net start "TermService"
net start "SharedAccess"
net start "stisvc"
net start "lanmanworkstation"
Save the file and rename it to "startnet.bat"
You will now have two batch files that will start and stop the main services used for your internet.
Go to Start > Run > type services.msc and you can look up each service in the above batch files for a description of what each one does.
If you are unsure, make a back up, use at your own risk!
I normally set all the above services to "Manual"
When you run the stop batch file a cmd window will pop up nd show the progress, a couple of the services will ask you if you want to stop then, type a y and press enter for each one.
Test your latency again with all the services stopped in your new hardware profile. When you go to your normal profile, use the start bat to restart the services so you can use the internet.
It also helps a lot to disable all programs that are running at start up in your audio profile, you can do this with a program liek startright :
http://www.joejoesoft.com/cms/showpage.php?cid=113
You can enable and disable programs at will using this simple prog, instructions on the site.
This post is a bit random and should point you in the right direction, it's been a long day but hopefully some of the above helps! I will try to add some more tomorrow if I have time!