I have a new build with a Z77 Extreme4, i5-3570k, 16gb g.skill, intel SSD, reusing a Radeon HD 5870. Running Win 7 Professional with SP1, patched to latest.

Bios 'most current version' when checked.

Everything works quite well, but when I boot windows, and log in, the system has no network access for up to 20 seconds. Any app auto-starting (dropbox, steam, etc) fails at it's first attempt to connect.

Windows reports looking for network, then reports an error, then gets connectivity.

This happens with a static address or a DHCP address.

I have this driver: Broadcom_Win8-64_Win7-64_Vista64_XP64(v15.4.4.1_64Bit)

I am puzzled what could be causing the problem. None of my other wired computers experience this delay, so I doubt it's my network.