You're installing Windows 7 or Windows Server 2008 R2 to a computer using an optical drive. The computer isn't physically connected to any network. You notice following behaviors: It takes an excessively long time (up to 8 hours) to finish Windows installation; After booting to Windows desktop, sluggish behavior is encountered such as delayed input response or erratic mouse movement. "This issue has been seen with computers with Intel Gigabit ET Quad Port Server Adapter NIC installed where the computer isn't physically connected to a network. The in-box driver for this card has a known issue where it may continually try to access NIC hardware while it's in a lower power state (D3). NIC doesn't respond and driver continually tries to access NIC. This affects system performance, either manifesting itself as increasing the installation time of Windows or causing sluggish behavior once booted into Windows," explains Microsoft.
In order to actually resolve the issues entirely, users need only grab the latest drivers (11.4.7 or later) from Windows Update, and update their machines.