DFM is not a general purpose trap receiver. It mainly relies on SNMP and ICMP polling to build its events. The traps that it does process or pass through can be found at http://www.cisco.com/en/US/docs/net_mgmt/ciscoworks_device_fault_manager/3.0/user/guide/TrapFwd.html . Therefore, for DFM to detect a power supply failure, polling must pick up the fault condition. The specific condition DFM checks will depend on the type of software running on the 6500.

As for threshold monitoring, you could use the CiscoView Mini RMON manager to create an RMON event/alarm provided the device is supported. Mini RMON typically only supports switches, but a few router classes are supported as well. A more general purpose monitoring tool is the new Health and Utilization Monitor which is an addon to LMS 3.0.1 (a free 90-day demo comes with the 3.0.1 installer).

Alternatively, you can manually configure RMON events and alarms on IOS devices using the "rmon event" and "rmon alarm" commands (see http://www.cisco.com/en/US/tech/tk961/technologies_configuration_example09186a0080094478.shtml). Or, if your device supports it, you could use the Embedded Event Manager to watch your bandwidth utilization and send a syslog, SNMP trap, or even an email from the device to alert your operators (see http://www.cisco.com/en/US/docs/ios/12_4t/netmgmt/configuration/guide/t_eemo.html).