Latitude E5440 and SCCM 2012 SP1 PXE boot

We use SCCM 2012 SP1 for extensive imaging in our K-12 environment, with DCIP 3.1.0. We typically install either Windows 7 or Windows 8, x64 (sometimes x86), and have imaged hundreds of computers, laptops and netbooks this year.

I just received a couple of Latitude E5440 laptops and am trying to get them imaged, and they are not working as our other machines do (we also have 5420's and 5430's in our environment). They shipped with Ubuntu - we ask for a minimal OS because we have an enterprise licensing agreement from Microsoft, but this is the first time I've seen one arrive with Linux.

I have imported the following driver packages into SCCM under Software Library -> Operating Systems -> Driver Packages , using the Dell Import Client Driver Package tool:

• E5440-Windows7-x64-A01
• E5440-Windows7-x86-A01
• E5440-Windows8-x64-A07

I have also used the Dell "Import WinPE Driver Package" tool to add the WinPE 4.0 A02 drivers to both the x86 and x64 boot images.

There are multiple task sequences deployed to the "Unknown Computers" and "All Systems" collections.

Behavior: the laptops:

1. PXE boot just fine
2. Load the x86 boot image (very typical) which had the WinPE drivers added to it
3. Flash the WinPE 4.0 logo (blue window icon)
4. In WinPE, I see Starting Up, followed by Preparing Network Connections in the smaller dialog boxes.
5. At this point, the dialog boxes disappear and I see only the grey screen for a few minutes, at which point the laptop reboots.

Can anyone point me in the right direction? I may be missing something because I haven't added new drivers in about six months.