X-RAY TIMING IN 1E-1740.7-2942 AND GRS-1758-258

We report on deep observations of the Galactic bulge sources 1E 1740.7 -2942 and GRS 1758-258 with the Rossi X-Ray Timing Explorer. These obj ects form a class of two, showing radio jets, very hard spectra, and p ersistent emission. Here we show that their power spectra are also sim ilar: flat-topped noise, breaking to a power law, with a pair of weak, harmonically spaced quasi-periodic oscillations above the break and a n integrated rms variability of similar to 20%. We discuss to what ext ent these results can be considered support for the identification of both as black hole candidates.