This does not mean that the computer was not infected.

Did you remember the name of the system files that were infected?
Any error message in the blue screen or before it?

You need to have avast installed in the other computer.
The files are in this folder by default: C:\Program files\Alwil Software\avast4\Data\Chest
The original name/path will be displayed in the new computer Chest and the files will be ordered by the number of the file name into Chest folder (All files, including the clean ones into the System folder of the Chest).