Hi Sally,
Cable problems can be much more complicated, and to cover all the possibities would require a small book, especially if you're having latency problems, (slow response time). A cable modems doesn't handle data like a regular ethernet card, for example.
Unlike ethernet cards, cable modems are not allowed to transmit on demand. Hundreds of cable modems have to share a single upstream channel frequency and none of them can hear each other's transmissions. If more than one cable modem were to transmit at once, the UBR, (Universal Broadband Router), would not be able to understand either of them. Consequently, all cable modems must remain silent except during allocated time slots, (measured in microseconds), as designated by the UBR. IOW, your computer has to request a time slot during which it can send an information packet, and it can only send packets of information during the pre-assigned time slots that are allocated by the UBR.
Do you know how to "ping" your network connection? Here's an answer to a similar queston that appeared in the Jan., 2006 issue of PC World, and it offers a relatively simple way that can be used to analyze a cable problem by pinging the connection:
http://www.pcworld.com/howto/article/0, ... 180,00.asp
You didn't mention the type of problem you're having, but if it's slow response, then viruses or spyware could possibly be a part of the problem, as discussed in the article.
If you'd like to read more about analyzing cable modem problems, there are some pretty good information sites available, but the dialogue tends to be kind of long-winded and detailed in places. This is a pretty good one:
http://homepage.ntlworld.com/robin.d.h. ... tency.html
I hope this helps.
Love,
Wayne