After splitting the Sharks' defense, Alexei Zhamnov had a shot glance off goaltender Evgeni Nabokov and bounce to the right faceoff circle, from where Amonte put the puck into an open net.
Rookie Mark Bell and Eric Daze also scored for Blackhawks, who concluded a 4
Zhamnov collected two assists and Jocelyn Thibault made 26 saves to secure his 12th win, tying Calgary's Roman Turek for the league lead.
San Jose forced overtime on defenseman Jeff Jillson's power-play goal with 3:17 to play in the third period.
Chicago took a 2-0 lead midway through the second on goals by Bell and Daze. But San Jose cut the deficit in half late in the second when Scott Thornton scored his seventh goal.
The Sharks are winless in their last three games (0-1-1-1).