The network cable I have connected to my computer at work is green like all the others in the office but my Connection is heaps slower than everyone else. We have 5 pcs running xp and 7 pcs running win 7, but mine is the only one that is slow.
It's probably a hardware related problem. The other (faster) computers may be ones that have faster CPUs. Also, the amount of RAM makes a difference. So will the video card. Some computers rely on on-board video (usually slow), whereas some may have an added video card (usually faster).
Do you have the specs for your computer and the spebs for the other computers?