  We investigate the timing behavior of XTE J1550-564 with the Rossi X-ray
Timing Explorer (RXTE) as the source made a transition to the hard state during
the decay of the 2000 outburst. We detect a high frequency QPO at 65 Hz in one
observation with a fractional rms amplitude of 4.9%. This is the first time
that a high frequency QPO has been detected in a transition to the hard state
during outburst decay. We also observe low frequency QPOs in the 0.36-4.1 Hz
range and rich aperiodic variability. The changes in the temporal properties
during the decay are very similar to the state transitions observed for other
sources. We find a correlation between the QPO frequency and the break
frequency in the continuum power spectra. We investigate the energy dependence
of rms amplitudes of the QPOs. We compare these timing properties with those
previously observed for XTE J1550-564 and other Galactic black hole candidates
and discuss the implications for QPO models and black hole accretion.
