>>> Troubleshooting latency problems <<<
Things that you can possibly remedy are:
Network configuration of the PC:
Poor latency can be caused by unnecessary network services or protocols being active in the PC (putting unnecessary traffic on the upstream), or by duplex mis-matches between the PC's ethernet interface and the cable modem's. See Network Configuration Tweaks for what you can do to minimise these effects.
http://homepage.ntlworld.com/robin.d.h.walker/cmtips/tweaks.html#cfg
(Network configuration Tweaks - too long to cut and paste - can be found about one-third down the Web page pasted above.)
Background applications in your PC putting traffic on the network without your knowledge. For instance, P2P applications can generate traffic even when they are just sitting in the system tray, and spyware might be totally invisible.
Cable problems with the ethernet or USB connection to the cable modem.
Cable problems with the CATV connection to the cable modem (tighten it).
Avoid hitting the upstream rate cap: the solutions are the same as the solutions listed to Simultaneous download and upload performance.
http://homepage.ntlworld.com/robin.d.h.walker/cmtips/tweaks.html#cfg
If your latencyproblems occur in online games, see On-line gaming performance issues.
http://homepage.ntlworld.com/robin.d.h.walker/cmtips/games.html
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The preceding came from a very thorough article, described and illustrated nicely, discussing troubleshooting latency issues:
http://homepage.ntlworld.com/robin.d.h.walker/cmtips/latency.html
REMOVE SPACES from the pasted URLs.