[RESOLVED] 2nd Opinion on a MOBO failure

[musicman7722]

Greetings: I have a Dell OPT 260. Today it stopped being able to connect to the network. I have proved the line is good to it and have since replaced the Dell with a working one (oh did I mention it is the Presidents PC). I feel it is the MOBO but before I trash it I'd like a second opinion. Here is what I've done. First I tried a new NIC. Int. thing is that the nics (old and new) show a good connection but the OS cannot get an IP. I have reloaded the OS with a clean format and still same issue. Finally I pulled the battery out of the mobo and reset it thinking maybe a mobo virus. Rare but known. Anyway none of these issues has resolved the prob. So I feel the mobo is gone. it works in every other aspect but this. Any thoughts? Chris

[slgrieb]

Somehow, I doubt this is a mainboard or NIC issue. I'd be looking at cabling issues. A cable tester or the idiot lights on a NIC may show a good connection but that isn't always true. Typical NIC signals are down around the 100 milliamp range and so it doesn't take much in the way of electrical interference to block data transmission, no matter what the basic tests show. I would check to be sure that your patch cables and keystone jacks don't have any loose crimps, or any cables that have untwisted a bit. If the cable has untwisted, the impedence jumps up (especially on the Green/Receive pair which is split) and creates a reflection point which can prevent data reception.

[musicman7722]

Carot: Thank you for your reply. Interesting idea, I had ruled out a cable issue as I tried a usb nic in the ailing PC with no change and a new PC in the old PC's office and network connection worked. Any further thoughts? Chris

[Guts3d]

We had a weak power supply do that for a Micron, might be worth a shot. Everything else worked flawlessly.