I installed Steam on Linux just to try it out, but I ran into the problem that when downloading games, the download speed wouldn’t climb above 15-20 kbytes/s. I tried switching download servers, switching from Wi-Fi to a wired connection, but nothing worked. Then I started searching online for solutions, which led me to the following steps that fixed my problem.

In a nutshell, the problem is that the Linux Steam client queries DNS nameservers too frequently, which quickly overwhelms the network. The solution is to install a DNS cache on the system, which we can do as follows:

On Ubuntu:

apt-get install dnsmasq

On Debian:

aptitude install dnsmasq resolvconf

Once installed, restart Steam and it should work now.