Gib has the stolen hard drive attached to his notebook. However, he only attached the data cable, not the power cable. Whatever he wants to analyze, it wouldn't work.
Before Tucker takes the hard drive, he, for whatever reason, also unscrews the cover of that drive. This basically renders it useless since the platters are now covered in dust from the air. You can even see the dirt and fingerprints on them.
Gib says that he cracked the firewall when talking about the data he just extracted from the hard drive. That term doesn't apply in this situation, he would have broken the encryption of that drive.