The answer is more simple than some of the other speculations here: the laptop display was only ruined when exposed to the Martian atmosphere. When the liquid in the laptop display "froze or boiled off", it was outside the airlock (as shown in the quote). However, when he downloads the data from the power loggers, there is no indication that he is outside in the Martian atmosphere (the book doesn't say either way). He probably dragged the loggers into his makeshift bedroom (built from the Hab canvas) before attempting to download data. This was the same location he used to perform calculations and trajectories, watch crappy seventies TV shows, etc. He was able to use the laptops as long as they were not exposed to the thin, cold atmosphere outside.

In addition, it is a common theme of the book that NASA standardized absolutely everything, so one could safely assume that all the laptops were the same model.

The answer is more simple than some of the other speculations here: the laptop display was only ruined when exposed to the Martian atmosphere. When the liquid in the laptop display "froze or boiled off", it was outside the airlock (as shown in the quote). However, when he downloads the data from the power loggers, there is no indication that he is outside in the Martian atmosphere (the book doesn't say either way). He probably dragged the loggers into his makeshift bedroom (built from the Hab canvas) before attempting to download data. This was the same location he used to perform calculations and trajectories, watch crappy seventies TV shows, etc. He was able to use the laptops as long as they were not exposed to the thin, cold atmosphere outside. He learned his lesson after his first experience and never took the laptops outside again.

In addition, it is a common theme of the book that NASA standardized absolutely everything, so one could safely assume that all the laptops were the same model.