1. Is the startup of the computer normal? You see clear white text on a clear black background?
2. Does your computer act in any weird way otherwise, or is everything ok? Doing texts or games etc.
3. If you have a laptop, or even with a desktop, you could try it in a friend's apartment.
4. Installed any new hardware or software lately? New drivers?
You see, it can be almost anything. If you have warranty, I recommend what I usually recommend: service. That way you will get it fixed. To give you one example of varieties,
http://answers.yahoo.com/question/index?qid=20111006164146AAjU0iN If it should work well in another place = another connection, contact your Internet provider.
Personally, I suspect a hardware failure, viz. network card. Not sure, though.
All of the very best.
