This is the 10813th most frequent Polish word.
działały
"Worked" or "functioned" (past tense of "działać").
The word 'działały' here indicates that the computers functioned or operated in a certain way in the past.
Komputery działały bardzo wolno wczoraj.
The computers worked very slowly yesterday.
Here, 'działały' refers to functioning effectively or efficiently in the context of machines.
Wszystkie maszyny działały sprawnie na początku projektu.
All the machines operated efficiently at the start of the project.
In this sentence, 'działały' describes the persistent and continuing action of the engines functioning during the mentioned time.