Tecra M9-136 - BSOD during Vista SP2 update

Question

Tecra M9-136 asked this morning to update to Vista SP2 and during the process the BSOD 0x0000007E arrived. Restarted in Safe Mode and the installer continued and then finally reported that the update had failed - and reverted to SP1. This took most of the morning.
It will start in Safe Mode but on a normal boot-up, Vista SP1 gets through the fingerprint recognition and then fails with the same BSOD (it doesn't get as far as displaying the desktop).
The laptop has BIOS level 1.80. I've tried in Safe mode to install 1.90 but it tells me that the battery has insufficient charge and the power adapter isn't attached. Both untrue.
Stuck - need advice. Could this be a hard fault? Can't see how I can update anything if it's a soft fault.
thanks

Answer 1

The message with the BSOD mentioned checking BIOS and driver versions. Anyway, no change made to that.,
I tried System Restore but the only available restore point was the SP2 installation. I thought Vista was supposed to save a restore point every 24 hours even if nothing new had been installed.
I've now found in System Information / Windows Error Reporting several messages like this:
28/09/2009 12:08 Windows Error Reporting Fault bucket 0x7E_NULL_IP_DRVNDDM+57bd, type 0
Event Name: BlueScreen
Response: None
Cab Id: 0

Problem signature:
P1: 
P2: 
P3: 
P4: 
P5: 
P6: 
P7: 
P8: 
P9: 
P10: 

Attached files:
C:\Windows\Minidump\Mini0928 09-04.dmp
C:\Users\me\AppData\Local\Te mp\WER-75660-0.sysdata.xml
C:\Users\me\AppData\L ocal\Temp\WER7D78.tmp.version.txt
& #x000d;
These files may be available here:
C:\Users\me\AppData\Local\Mic rosoft\Windows\WER\ReportArchive\Report06d1c4b5