important compatibility question

[rmathney]

I just got comcast 2 days ago and got it working perfectly on a laptop but my desktop (my better computer, which worked perfectly with road runner in NYC) won't connect at all. It's almost like it can't communicate with the cable modem at all. I have 2 onboard ethernet ports (with my asus a7n8x deluxe v2.0 - 1008 bios). I thought those might be bad so i got a cheap belkin NIC and that doesn't work either. Does anyone know of some compatibility issues with VIA chipsets and my Motorola SB4100 cable modem? I was flying though some threads on different forums and someone said briefly that there might be some problems with via chipsets (can't find where it was posted) but I can't seem to find anything else on this. Thanks.

 

[Peter]

How should the core chipset influence the NIC? Besides, the A7N8X doesn't even have a VIA chipset ...

Can you ping the cable modem? Does that modem even contain a router, or does it allow only one machine to be connected at a time?

 

[rmathney]

ya i knew it didn't have a via chipset, but for some reason it escaped my mind while typing this post in frustration. When i saw that post somewhere about the via chipset, i was thinking if there was a problem with via chipsets, there could be one with nforce.

anyways, the modem only allows 1 machine to be connected at a time, and i can't ping it or get to its settings (192.168.100.1 - i can get to the settings like this on the laptop). I make sure to power cycle properly when i connect my other computer, and i've tried 6 or 7 ethernet cords (including the one that works on my laptop) but i still can't communicate with the cable modem at all (doesn't matter which of the 3 ethernet ports i use).

 

[Peter]

hmmm ... can you network the two computers you have (using a crossover cable)? You need a method to assert your desktop computer's networking works at all. If none of the cards and onboard connectors you used are working, the problem might be in the higher layers of Windows network driver stack.

 

[Concillian]

Your problem is not likely with the hardware but with the network setup.

Have you setup the networking settings EXACTLY the same for the desktop as they were setup for the laptop?
Do you have some remnants of some Roadrunner setup that the Comcast doesn't like?

I'm just finding it really hard to believe that it's a problem with the NICs when 3 different network cards all fail with the same failure mode.

 

[rmathney]

setup is exactly the same in both laptop and desktop, roadrunner required no additional software/settings but that wouldn't matter because I'm working with a fresh xp install. The 2 computers can be networked using my router (haven't tried using crossover cable though) so the desktop's networking seems ok just not with that cable modem.

Comcast has pretty much told me that it's my problem now and not theirs. I've exhausted whatever help program they use...i've probably been through their entire routine 3 times or more now.

I'm still convinced there is some compatibility issues, whatever they may be, between the cable modem and the hardware on my computer. But comcast said if they were to send a technician with a new cable modem they would charge me $50, even if it didn't work.

edit: just did a 3com test (onboard port) and during the NIC test, it failed and said something about not being able to receive a frame during the loopback test. This is the same thing i'm seeing when i check out lan status...packets get sent, but packets received is always 0.

 

[batmanuel]

I'm having zero problems with almost the same setup (A7N8X-DX, SB4100, Comcast) so compatability is not an issue.

Have you tried throwing a router on the modem to see if it can communicate with the modem? That would allow you to narrow down if the issue is in the modem or the desktop's network config. If the router can talk to the modem, and the latop can talk to the router, but the desktop can't then there is most likely something seriously amiss in your network settings.

I'm also assuming that the desktop is set up to automatically obtain and IP address from the modem, right?

 

[rmathney]

ok the router is working great, and so is the laptop (connected through the router), so both of these can communicate just fine with the cable modem. so it must be something with my desktop. the settings are default after the fresh install of xp and they're exactly the same as the laptop network settings. I just can't figure out what the problem could be.
i appreciate all the help and suggestions so far. thanks.

 

[rmathney]

everything works great now with the router installed (tried this 6+ times). not quite sure why, cuz the desktop connected directly to the modem still doesn't work. any ideas why?
anyways, thanks so much for the help

 

[tcsenter]

Unplug the network cable from your computer, go to Device Manager, right-click on network adapters and click Uninstall. Shut down your computer (not restart). Unplug the power from your cable modem. Power-on your computer, let Windows redetect the hardware and install drivers. When your network adapters are installed again, shut down your computer. Connect the power to your cable modem, connect the network cable to your onboard LAN, power on your computer and give Windows a minute to load completely.

Works for me when I encounter a 'dead' LAN connection after swapping motherboards.