Well, for starters, this board is not supported by/with Windows 10, so I am not surprised to hear of this issue. In this case though, I am thinking it likely that this is a BIOS issue - that the BIOS is leaving the board's MAC in a bad state. If this is the case, considering that this board is in EOL status (and Intel has exited the Desktop Boards business), no BIOS fix will be possible.
Are you using PXE boot? Even if not, you may have it enabled. Try disabling it. This is done in the Boot section of BIOS Setup.
Hope this helps,
I was surprised, as Intel provide Windows 10 drivers for the NIC chipset. Also in the last few years I've never had an issue with a core chipset like this failing to work in a newer version of Windows. Scanners and printers, yes, but not audio or NIC.
The majority of these machines don't have PXE boot enabled, but one that does doesn't seem to exhibit the problem. I wonder if this is because it leaves time for the chipset to come live.
I'm trying a second fix also, to disable fast startup in Windows 10. This is done using a registry change. Should be evident Monday morning if this has worked. http://www.edugeek.net/forums/windows-10/171184-disable-fast-startup-power-management-option-via-gpo.html