Internet is slow/unreilable under Ubuntu but not Windows, even though they're on the same machine and my network is fine.

I've recently installed Ubuntu to make software development easier for school. The only problem is that the internet is very slow/unreliable even though my network is fine. For example, I have to click links multiple times for them to load, installing software packages often fails unless I try 3-4 times, etc. Under windows, my internet is fine and works as expected. My network isn't the problem as I've simultaneously used the web from my laptop and desktop, with my laptop running Windows and my desktop on Ubuntu, and the results are as described. My desktop is connected via ethernet to a router. Again, I only have issues under Ubuntu, so I don't suspect its a network problem, but it may be a configuration issue in my Ubuntu network preferences or some sort of driver being out of date for my mobo.

thanks,
Omar