Cable Modem possible problem

[petal16]

Hey I got a Surfboard cable modem and use comcast. Well sometimes my internet goes down which I understand but lately it has done it alot and it takes about 2 to 5 minutes or unplugging and resetting a few times before it works again. My question is how do I know if my cable modem is playing up? (Do they do that or just go kaput?) or ifs its just a comcast thing.
Are there any sites to test a cable modem. Seems like I gone through 3 computers and the one same ol' modem. I don't wanna get fixated on it being the modem if it's just comcasts problem but how will I know for sure. Its not like I can go to comcasts site when my internets' down.
Any info would be appreciated. Thanks. I have read the forum alot and usually fix my own problems and I find nearly all my answers here. But just subscribed recently.
Thanks again for any input.

[glc]

Is the modem on its own dedicated cable coming off the very first splitter in the line coming into the house? You could be getting excessive attenuation - or you could have a bad cable somewhere. Motorola modems are excellent, but it is possible for one to go bad.

[petal16]

I am using a Lynksys router to share internet access with our laptap. Plus I have media center. So I have the cable coming out into the modem, computer and split for the media center. One of the cables is very long..maybe 9 or 10 ft and the splitter looks a little 'cheapish'. I guess I could have excessive attenuation as you put it. Can this cause intermittant cable loss? I guess my main question is still is there no way to check the modem? Or should I go buy new cables and a splitter and try that first?

[glc]

You cannot do that. There can only be ONE splitter between the street and the cable modem, and that should be the one the cable company installed when installing your service and cables. All TV's, etc. have to be fed from the other side of that splitter.

[petal16]

Ok let me rephrase..coming out of the wall my cable goes to a splitter, one goes to the cable modem the other to the puter. Everything works fine, has been for a about a year now, my original problem still stands, At least once every few days my internet goes down, and my question was is it tired ol cables, cheap splitter, cable modem or comcast. I will ask again are there any ways or web sites to check to see if your cable modem is ok as I have had it for 4 years or is it just heavy traffic from comcast?

Btw, comcast never touched my computer, I had a line in the Computer room already when I moved in. They made sure the connection in the room worked from the wall, gave me software, it was all installed ok and has been working for 4 years now. I got a new computer last year, with media center, hooked everything up, thats been ok for a yearish but my problem is still every couple of days in the last few weeks the internet goes down, the modem tries to connect and it takes forever, or I unplug it and resets.

[glc]

And I am saying to disconnect that splitter in your room and connect the cable directly from the wall jack to the cable modem. I am not saying that this IS the problem but you have to start troubleshooting SOMEWHERE using a logical progression.

[cadlewv]

Agree with glc, in as much that if your signal from the tap isn't sufficient, an additional splitter inside your house could drop your signal to unacceptable levels.

Whenever your internet goes out, turn on the television, or tune in via your tv-tuner card and see if the picture is fuzzy, or noticeably worse. Cable signal decreases with heat, so in the summer (especially the heat of summer) cable companies have to increase the signal to accommodate the signal loss. In the winter the signal goes through the roof, so they have to turn it down.

Hooking the cable up directly, bypassing the splitter would be a good place to start. If it's worked the way you had it hooked up for 4 years and now won't.... then you plug the cable directly into the modem and it works, consistently, then your signal has probably suffered a loss. Could be the heat, could be squirrels chewing on your lines, could be construction down the road.

Got to start somewhere.