Ok, I have asked this problem to every one that I work with and have come across that works in the tech industry. No one can seem to figure it out. For about the past 3 years my computer NIC has had to be set at 10Mb half duplex to maintain a conection, anything above that and it will not conect. If it is set to auto it constantly conects and disconects. I have replaced the cables and the NIC several times. None of the other computers on the network had this problem till I built a new computer and it does the same thing. I have replaced the NIC, cabling, power supply and ran a dedicated power circuit from the breaker box and none of it seems to make any diference. My router/switch is a linksys BEFSX41, the 2 computers in question are in the same room as the router/switch. All of the other computers in the house have no problem, even my laptop has no problem when it is in the room with the others. When ever I am transfering files between computers and one of them is one of the computers in question here the nic tops out at about 25% of the 10Mb conection and the graph looks like a bad saw blade. Larger files are virtualy impossible to transfer because it looses conection before they complete.

I admit I am not knowing a proper solution to this but could you please change the port in which you N/W cable is connected to the switch (the switch port i mean). If the prob still persists then I think you can try out with a new Motherboard or atleast change the PCI slot.

I have tried every port on the switch. I have changed the pci slot to every available on on the computer and have also changed the NIC.

then your ethernet controller might be out...have u tried with a new Mobo

ok, I found the problem, I have 2 bad linksys routers at my house. I Just bought me a new buffalo router and the problem is fixed. I have seriously lost my faith in linksys products. Allmost every call I get for networking problems turns out to be linksys problms. This month I have had to replace 3 bad wrt-54g's. A coupple of months ago my company when called to do new home network installs have gone to using buffalo routers and have had no problems out of them. I was allways a big linksys fan because they where cysco but it seams to me they whent to cheap with linksys.

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