to CF
It sounds like you are frustrated but, unless I'm missing it, you haven't actually said what your problem is!
From the title, can we deduce that your broadband is sometimes slow. Slow measured by what - browsing, downloading, gaming?
Have you used any of the speedtests available (such as the CF one above)?
What speed service are you signed up to?
Are you connected via a cable modem or STB?
How does your PC connect to the modem/stb - Ethernet (RJ45) cable or USB?
What OS is the PC running - XP Home?
Is anything else running on the PC when the network is slow?
Hopefully the answers to these will help us tie down your problem.