890B (HP)

After giving Luna the laptop (Section 4 achievement) you will have a timer, and are tasked with finding welding equipment. you will also now be able to run with so run into the 3 or 4 white cubes in the atrium, then head upstairs and right to the calculus lab, then left and down into your room to get the tools. Head back to Luna, where you will then need to interact with a computer interface to proceed.
Flick up, and input 'help', then to run the command (do after every step). Then type:

initpowercheck
flushpower
checkboardstats
runsecuritydiagnostics
beginpowerrestore
exit

each step will take a little bit of loading (because who doesn't love dealing with a slow computer), but exiting unlocks section 5

Section 1: 0:45
Section 2: 0:55
Section 3: 1:45
Section 4: 3:05
Section 5: 7:20
Section 6: 14:50
Section 7: 17:05
Section 8: 22:40
Section 9: 22:55
Section 10: 26:30

Achievement Walkthrough: