Have you had any luck with this? I'm having the same issue (E5520) and its something to do with the drivers.
Using the latest E5520-win7-A03-R316474 (x64). With driver detection it crashes and there are 2 issues from what i can see:
1) the dell touchpad driver is marked as boot-critical and fails to load during the Windows setup (Setup Windows and ConfigMgr) disabling this driver helps. evidence of this is in the setupact.txt
2) it still crashes at the same step with the same 0x80004005 error however it appears the network drivers have not loaded as it has no IP address.
to fix #2 ive tried:
-latest drivers provided by dell, within the CABs and via seperate download.
-latest drivers direct from Broadcom
-Intel drivers for the Mobile Intel® HM65 Express Chipset (Intel 82579V Gigabit Ethernet)
edit: spoke too soon, it's not fixed.