dsl modem connection question

I assume that there is a global standard for connection leads, if there isn't then what follows will no doubt mystify some readers.

Partner's ex has just got a new PC to replace one that died not too long after switching to dsl. The new PC would only connect for a few minutes before dropping the connection, my partner spent some time "attempting to fix it" (I have no idea just what she did or didn't do) before we went on a holiday trip last week, she also spent more time doing something to it yesterday.

My first look at it was earlier today, a couple of things I noticed -
1) the PC was connected to the modem via a red cross-over lead which I think (but am unsure) is the root of the problem (I have one that connects modem to router). Could someone confirm or correct me please?
2) there is no network or ethernet card to be found in device manager leading me to think that the card has either been uninstalled during her fix attempts or has been physically damaged possibly due to prolonged use of an incorrect lead. Again if someone would be so kind as to either correct or confirm my guesswork, or even provide other so far unconsidered options.

If the use of an inappropriate lead can cause physical damage it would go a long way towards explaining why the old PC died, also if I am right then would this cause some sort of problem with the modem itself that would also make other computers connected to it at the same time have connection problems?

No connection light shows on the modem regardless of what sort of lead is now connecting the two but the modem does function perfectly well as a laptop will quite happily surf online using it.

 

by 'lead' i'm assuming you are talking about Cat5 networking cable? (ethernet).

i've never heard of a bad cable physically damaging anything, so I doubt thats an issue. Is the Network Adapter a separate PCI card or is it integrated on the motherboard? (you can tell by the location on the back of the computer if you dont want to take the side off)

if it is integrated, it might be turned off in the BIOS? if it is a PCI card, it might have gotten loose from repeated cable issues. Try unplugging the PCI card and putting it back in.

if you dont see anything in device manager and the card is plugged in (or turned on via the BIOS) then you might have a dead network adapter.

also, when you mention a laptop working fine, is this using the same network cable as with the computer? (to rule out a faulty cable as well)

 

There is. You'll find it described at <http://www.bluemax.net/techtips/networking/Wiring_Tips/Wiring100TX/colorcodestandards.htm>. Note the difference between straight-through and cross-over cables.

You mention that you're using a crossover cable to connect your machine to the modem. I assume you are referring to an Ethernet cable. If so, it should be a straight-through type, not a crossover. The latter has a reversed pair of connections within it.

An incorrect cable isn't likely to damage the hardware -- but might cause the system to fail to set up the card correctly.
Once you have the right cable attached, you might re-installing the network card.

 

Apologies for the incorrect terminology, yes, I meant the CAT 5 ethernet cables.

Thanks to both to putting me straight on my faulty guesswork.

I didn't open the case as it's a new PC, not mine and of a new design to me - Shuttle (?), about half the height of the cases I've got.

I've advised them to send it back to get it fixed, whether I'll get to know just what the problem is I don't know.

Many thanks for the replies, I'm now better informed than I was before asking.

 

a week goes by ...........

dsl modem has been checked out - fine
PC sent back for repairs
laptop has been happily online the whole weekend
PC returned today, plugged in, works fine (using correct cables)
boys come in spend a few hours playing online game (Wolfenstein)
they finish playing, switch off, go out
now neither laptop or PC can go online, neither seperately nor together

any thoughts or suggestions? It's an hour's drive from here so I won't go there unless there's a reasonable chance of doing something practical.

Surely it can't be anything to do with the machines themselves?
Modem seems unlikely as it's been checked out and was working fine up until the PC was switched off.

But why would the net connection disappear after the PC was switched off? Coincidence or cause (somehow)?

Maybe problems with the phone line itself? No idea how to check that out.

But it still seems very strange that the connection is fine until the PC is switched off????

 

maybe try a simple reset of the modem and router?

unplug the power from both modem and router. Plug back in the modem, and then the router.

 

as far as I understand everything had been switched on, off, unplugged, replugged without any success

whilst doing a google I came upon what might be a very simple (but probably rarely considered) solution which is to move the modem well away from any other electical equipment, I won't know until the weekend whether it has been successful but it could be a very simple solution for others suffering similar problems.

As the problem only reappeared when the PC was replaced in it's position about 6 inches from the modem it really could be that simple.