The following will allow you to add additional drivers to Windows Vista/7, and Server 2008. (Also ConfigMgr/MDT boot media.)
First create a directory on your C: drive called images. Within that folder create a folder called Drivers, offline, and Source. Next open up the Deployment Tools Command Prompt. At this point you need to copy the wim file you want to modify to the C:imagessource folder. In this example we’ll say we’re trying to add additional drivers to an RTM Server 2008 R2 boot.wim. Now put all the drivers you want to add in the C:imagesdrivers folder. They need to be actual drivers with the inf files, not just executables that install the drivers.
Now at the command prompt, type
Dism /Get-WimInfo /WimFile:C:imagessourceboot.wim
It will now display all the images contained within boot.wim. Note the name of the image that you want to add the drivers to. When you run this command against a Server 2008 R2 boot.wim you should see the following.
Now you need to mount the wim image that you want to add drivers to. Run the following command.
Dism /Mount-Wim /WimFile:C:imagessourceboot.wim /Name:”Microsoft Windows PE (x64)” /MountDir:C:imagesoffline
Now you have two different possible command to run for adding drivers. The first command will only add the driver you specify. The second command will add all drivers in the Drivers folder and in sub directories.
Dism /Image:C:imagesoffline /Add-Driver /Driver:C:imagesdriversintelraiddriver.INF
Dism /IMage:C:imagesoffline /Add-Driver /Driver:C:imagesdrivers /Recurse
If you need to add an unsigned driver run the following command.
Dism /Image:C:imagesoffline /Add-Driver /Driver:C:imagesdriversunsigneddriver.INF /ForceUnsigned
Once you’ve added all the drivers you need, run this last command.
Dism /Unmount-Wim /MountDir:C:imagesoffline /Commit
At this point you can copy your boot.wim file back into the Server 2008 R2 installation source and you’ll have a boot.wim with all your drivers. I would also recommend adding the drivers to install.wim as well.