  Results are presented of extended and refined optical identification of 181
radio/X-ray sources in the RASS-Green Bank (RGB) catalog which have been
spectroscopically observed in the Sloan digital sky survey (SDSS) DR5. For 72
sources, the identifications for are presented for the first time. It is
confirmed that the majority of strong radio/X-ray emitters are radio-loud
active galactic nuclei (AGNs), particularly blazars. Taking advantage of the
high spectral quality and resolution and our refined spectral modeling, we are
able to disentangle narrow line radio galaxies (NLRGs), as vaguely termed in
most previous identification work, into Seyfert II galaxies and LINERs, based
on the standard emission line diagnostics. The NLRGs in the RGB sample, mostly
belonging to `weak line radio galaxies', are found have optical spectra
consistent predominantly with LINERs, and only a small fraction with Seyfert II
galaxies. A small number of LINERs have radio power as high as
$10^{23}-10^{26}$ \whz at 5 GHz, being among the strongest radio emitting
LINERs known so far. Two sources are identified with radio-loud narrow line
Seyfert 1 galaxies (NLS1s), a class of rare objects. The presence is also
confirmed of flat-spectrum radio quasars with the radio--optical--X-ray
effective spectral indices similar to those of High-energy peaked BL Lac (HBL),
albeit it is yet a debate as to whether this is the case for their actual
spectral energy distributions.
