The combo CAB has been discontinued. Download Dell Family Driver CAB files
For future releases & other users, I've tried this on the Dell D810; all drivers were present sans the Audio, Wifi, and Simple communication devices drivers.
Put this combo cab on our universal image, imaged a E6420, and was left with a "Mass Storage Controller" without drivers installed after sysprep setup.
This was the O2 Micro Controller and when I manually pointed it at the driver, got a warning that it was unsigned.
chipset\GVG3T\O2Micro\Win7\O2MDFw7.INF,"SCSIAdapter","O2Micro","01/03/2011,126.96.36.19932","O2Micro","O2MDFRDR","","PCI\VEN_1217&DEV_8231","HardwareID","O2Micro Integrated MS/MSPRO controller"
FYI, the second WMI query should be:
select * from Win32_ComputerSystem where Model like 'Precision M%'