See-saw shape on download test/low consistency of service

[clausiam]

So I've noticed if I run the test at Speedtest.net I always get a download speed shape
like this (normally actually more 'spiky' than this)


If I run the test at http://www.ispcompared.com/internet-speed-test.htm I get around 25-30% consistency of service on download (about 85% on upload) and a very spiky graph as well.

I'm on Comcast and I'm pretty sure this is something new and I do notice it on day-to-day internet use as well, not just in these tests. This is a wired connection, not wi-fi.

Any suggestions on where to go start troubleshooting this? On my PC/network card, on my router, my Comcast supplied cable modem or by contacting Comcast support (please NO!).

[BroadBand]

Stop using Speedtest.net for one. Run our tests for a couple of days and we'll check things out and get back to you.

[clausiam]

Ok, so I've run several of the tests - here's a typical result:


The saw-tooth shape and the low QoS matches the 'user experience' I have.

What's the first place to start troubleshooting for something like this?

[BroadBand]

That sawtooth pattern also indicates you might have been speed testing on a wireless connection or you windows network settings are messed up. Were you testing on a wireless connection?

[clausiam]

No, this is on a wired cat5e connection.

[disconnected]

What version of Windows are you running? I may have a patch that will fix this