I would recommend opening up a Command Prompt (assuming you're on Windows here) and doing this (assuming your router is 192.168.1.1):
ping -t 192.168.1.1
And let this run indefinitely. When visiting a web site that results in the problem you see ("connection was reset"), quickly look over at the window running ping and see if you see any errors/anomalies there (such as "Request timed out").
Alternately you can download
Ping Plotter which will effectively do the same thing (think of it like a repetitive traceroute) and I can tell you what configuration settings you need to change to increase polling interval + provide more details in case of errors.
You could also do the exact same (in another window, meaning two ping windows going simultaneously) with your cable modem, if it has a LAN-accessible interface. For example most Motorola cable modems will answer/respond on 192.168.100.1 (regardless of what your netblock/network size is), so
ping -t 192.168.100.1
. Likewise you can visit »
192.168.100.1/ to look at logs/signals stats/etc.. There's always the possibility your WAN port on your router, or your Ethernet port on your cable modem, is flaking out.
It would help me if you could tell me the exact models of everything you're using:
* Brand/model of NIC (you say "AMD 780G chipset" but this doesn't necessarily mean you're using an AMD NIC)
* Driver version of NIC
* Brand and model number of router, and if you can find it, firmware version too
* Brand and model number of cable modem
Finally, to answer your question literally: could this be hardware? Yes. Could it be software? Yes. I know first-handedly
Realtek has an awful history with driver-level bugs, and there are other NIC models out there which have similar driver-level quirks that manifest themselves badly with the rest of the IP stack. You'd have virtually no way of determining this without a network engineer being present in person to diagnose things, however. Troubleshooting network drivers is not an easy task.