Dell will never test and publish drivers to run a Server OS on a workstation or to run a client OS on a server, so 2008R2 is not supported on the 990.  However, unsupported does not mean impossible: In the absence of drivers from your PC's manufacturer, you can use one of the following: 1. Driver from the device manufacturer (in this case, Intel):[URL] 2. Windows 7x64 driver:    
The install went OK up to the point of activation which fails due to no network hardware being detected. I assume some drivers need to be installed, but there don't seem to be any W2008 drivers yet. Has anyone encountered and resolved this issue yet?
Windows 2008 64bit R2 SP1 not finding any network hardware for a Optiplex 990 
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