If you're on a Network, are there other computers, connected to the Internet also? And have you setup (with your ISP) to recieve multiple accounts, or are you all sharing the one connection?
Try this Tweak
-- scroll down and press 'Start'. Once it has completed, press 'Results'. Enter the details on the new page, and then press 'Recommend'. Now, read the information, and also, please scroll down, until you see the next: Still stuck? copy/paste this url:
Do as it says, and copy/paste the provided URL into your next reply, so that I can also see your results.
Once you have completed the Tweaker, then try plug your computer directly into your modem -- do you still have slower download speeds?
80kbps, the average is about 50kbps
What are the advertised speeds that you should be recieving?