  Based on a Chandra ACIS observation, we report the detection of an extended
X-ray feature close to the center of the remnant DA 530 with 5.3 sigma above
the background within a circle of 20'' radius. This feature, characterized by a
power-law with the photon index gamma=1.6+-0.8 and spatially coinciding with a
nonthermal radiosource, most likely represents a pulsar wind nebula. We have
further examined the spectrum of the diffuse X-ray emission from the remnant
interior with a background-subtracted count rate of ~0.06 counts s^-1 in
0.3-3.5 keV. The spectrum of the emission can be described by a thermal plasma
with a temperature of ~0.3-0.6 keV and a Si over-abundance of >~7 solar. These
spectral characteristics, together with the extremely low X-ray luminosity,
suggest that the remnant arises from a supernova with an anomalously low
mechanical energy (<10^50 ergs). The centrally-filled thermal X-ray emission of
the remnant may indicate an early thermalization of the SN ejecta by the
circum-stellar medium. Our results suggest that the remnant is likely the
product of a core-collapsed SN with a progenitor mass of 8-12 Msun. Similar
remnants are probably common in the Galaxy, but have rarely been studied.
