Desktop

I have tried this and it has helped. Go into the properties of my network places, choose properities from the network connection and remove the network adapter, tcp/ip, and anything else in the box. Reboot the system and reinstall the client for MS networks, ethernet adapter, tcp/ip and when completed, reboot. Go into Internet explorer and run the connection wizard for your connection. I would also reset the modem and the router.

Try scan your pc for viruses & spywares. some trojans can caused this.

You may also want to make sure that you temps are fine. I have seen may computers doing strange things just because the CPU Temp was a bit high. To fix this it can be as simple as cleaning your heatsink and fan

Yes Rick it has been my experience while dealing with networks most customers either have a virus or a bad spy ware problem. The hardware isn't the problem. Try running something like spybot search and destroy or another malware cleaner it should help you reduce and minimize some of the problems.

Try to check any IRQ,I/O,memory conflict by using 'system info' and 'device manager'. you can snach the nic from pc and uninstall the driver.Then put that into pc and install them.You can use 'system restore' for uninstalling driver.