Sudden Upload Speed Dropoff

Hi - hope this is the right place for this. My upload speed (tested periodically via the thinkbb speed checker) has suddenly dropped off from about 0.7 Mbps to 0.12 Mbps. Download speed is unaffected at about 9 Mbps. The computer is a desktop Windows Vista computer connected via ethernet cable to my router. Connecting a laptop to the cable I get download of 9 and upload of 0.7 which is what I used to get from the desktop. It can't be a problem with the cable therefore. I have trawled around trying to find an answer but have not had success. Any ideas anyone?

Have you installed anything like an anti-virus or ad-blocker recently? The Ad-blocker I used to use had a bug that dropped upload throughput by 50%. I know it sounds a bit weird for an ad-blocker to impact upload speed but they acknowledged it. Something to do with the way they hooked into the network stack apparently.

Edit: http://forum.admuncher.com/viewtopic.php?f=4&t=29391
and
http://forum.admuncher.com/viewtopic.php?f=4&t=680

Apparently they are claiming it's an artefact and not a real figure.

Edited by Andrue (Wed 30-Apr-14 16:07:22)

Also worth trying to find out the wireless connection speeds, you can have a different speed for the different directions

Thanks to you both. The desktop does not have wireless. The laptop wireless speeds are 9 down and 0.7 up - consistent with its wired speeds. I did put in an update to comodo firewall possibly around the right timeframe, but I also updated the laptop (win 8) to the same version. I can't see anything in the firewall settings that could slow it down. For no good reason I'm thinking this is a software problem.

It is not easy to diagnose problems such as yours.
First port of call would be to remove software recently installed.
Either using the Restore Point or Uninstall Utillity sorted in date order.

Remove and reinstall ethernet controller driver
Obtain usb ethernet unit for £3 ebay.

It's something in Windows. I dual boot the desktop machine with a Linux OS. Booting the Linux system gives me 9 down and 0.7 up as expected. So the problem is something in Win Vista.

Or your running a program thats using upload speed on windows something like a torrent client