Keep in mind that Microsoft drivers are often bum. DOA or just bad. There's other issues such as CODE 31 can be replicated if I had a new install but forgot to either install the motherboard chipset driver package or had the ethernet turned off in the BIOS.

To test if it's hardware I use one of the many free Live OSes like Linux Mint. And no, I just boot those from USB or CD/DVD since it's LIVE! and doesn't require installation.
Bob