"Driver power state failure" often refers to a problem entering or coming out of sleep. Maybe your PC is trying to enter sleep instead of shut down.
Go to Start>All Programs>Accessories>System Information to look for your BIOS version installed. Compare it to the latest BIOS version on the Toshiba site here which is 2.30 WIN:
Driver Details - Toshiba
If you have a lesser BIOS version than 2.30 WIN then I would run the Update, making sure to follow the instructions given closely since failng to do so can cause serious problems.
If you have the latest BIOS version then boot into BIOS setup by rebooting and tapping the key given on first screen for BIOS Setup. Qosmio has Toshiba BIOS and every unit with Toshiba BIOS can be enter using ESC > F1 key. Some Toshiba units have Phoenix BIOS and it can be enter using F2 button at the startup. Once there find the tab to reset the BIOS to defaults. Take note first of the SATA controller setting which should be AHCI.
Clear CMOS - 3 Ways to Clear the CMOS - Reset BIOS
There is another serious problem caused by ignoring the specific advice which was given you to use the latest official Win7 installer with SP1 provided in Steps 1 and 2 of
Clean Reinstall - Factory OEM Windows 7. This means that the very latest drivers were not in the installer and you may be struggling without drivers that are required to run your System.
I would either download the latest ISO for your licensed Win7 version in Step 1 and burn to DVD using the tool in Step 2 of
Clean Reinstall - Factory OEM Windows 7 to do it over, deleting all partitions during the booted install, or immediately install the Toshiba chipset from
Driver Details - Toshiba
I've asked for some consultation on this from one of our Blue Screen analysts.