Why do I get inconsistent timing reports from the Timing Analyzer?

Due to a problem in the Quartus® II software versions 10.0 SP1 and earlier, the Timing Analyzer may report incorrect timing results if your Quartus Settings File (.qsf) contains settings for the Timing Analyzer and any project setting in the .qsf is modified while the Timing Analyzer GUI is open.

To work around this problem, close and re-open the Timing Analyzer GUI after making any change to the project settings in the .qsf.

A patch is available to fix this problem for the Quartus II software versions 10.0 SP1 and 9.1 SP2. Download and install the appropriate patch from the links below:

• Quartus II software version 10.0 SP1
  • Quartus II software version 10.0 SP1 Patch 1.130 for Windows (.exe)
  • Quartus II software version 10.0 SP1 Patch 1.130 for Linux (.tar)
  • Readme for the Quartus II software version 10.0 SP1 Patch 1.130 (.txt)

• Quartus II software version 9.1 SP2
  • Quartus II software version 9.1 SP2 Patch 2.101 for Windows (.exe)
  • Quartus II software version 9.1 SP2 Patch 2.101 for Linux (.tar)
  • Readme for the Quartus II software version 9.1 SP2 Patch 2.101 (.txt)

This problem is scheduled to be fixed in a future version of the Quartus II software.