I did some work on a computer recently that had problems keeping an internet connection. Here's what happened. I turned on the computer and there was no wireless connection. After resetting the USB cable that connected the Wireless G USB Adapter (old linksys that still had the light blue on the box) to the computer the connection came back but only for a moment. I ran the windows connection diagnostics wizard from IE and it was able to find the connection. The connection held for about an hour and during that hour I updated Malwarebytes and ran a scan, it was clean. The virus scanner also turned up clean. After this was done Windows lost the connection. After a Windows reboot the connection was found immediately and it held the remainder of the time I was there. Given that this has been an issue for the client for some time I suggested purchasing a PCI wireless adapter. I'm under the assumption that there is a problem with the (old) wireless USB adapter or possibly even the cable it is attached to. Possibly not enough power?
In the end what I want to know is what else could be the problem?
Edit: I should note that this is related to a desktop not a laptop. If that matters at all.