Hi. I wonder if somebody has any insights about this particular problem I'm having. So I just upgraded the CPU from this system I build some time ago. It's got a Gigabyte GA-M57SLI-S4(rev. 2.0) motherboard. My old processor was an Athlon 64 X2 Dual-Core 5600+ 2.8 GHz. I upgraded to a Phenom II 940 3.0GHz. The upgrade went smoothly for the most part, everything seemed to be according to plan. Booted right up to Windows Vista 64-bit and everything seemed fine, except it wouldn't connect to the internet. When I clicked the Networking and Sharing Center it showed that it was connected to an unidentified network and the connection was local only. I rebooted the PC 2 or 3 times and the problem persisted. So I downloaded (from another PC) and installed the latest version for the onboard LAN adapter from nVidia, but the problem persisted. I then booted up to Windows XP, and the same problem was happening. It would not connect to the internet. Even if I manually set up IP addresses, DNS and all, it still will not go online. I then proceeded to remove the Phenom II processor and put the old Athlon back. This time the LAN adapter worked just fine, connected to the internet with no problems. If I put the Phenom II back, the problem comes back.
Does anybody has any idea of why this happens? It seems like the onboard LAN adapter of this motherboard doesn't like the Phenom II for some reason. Besides that, everything else works like a charm.
You seem fairly knowledgeable... so I'm just going to throw out a thought about the hardware interrupt. Maybe the two devices are stepping on each other's toes somehow. Never heard of such a thing myself, but it's the only thing that occurs to me.
We don't think much about interrupts these days, because it's supposed to be all taken care of and devices are supposed to play well together.