Diversity of the X-ray observations of dwarf nova are still not fully understood .
I review the X-ray spectral characteristics of dwarf novae during the quiescence in general explained by cooling flow models and the outburst spectra that show hard X-ray emission dominantly with few sources that reveal soft X-ray/EUV blackbody emission .
The nature of aperiodic time variability of brightness of dwarf novae shows band limited noise , which can be adequately described in the framework of the model of propagating fluctuations .
The frequency of the break ( 1-6 mHz ) indicates inner disk truncation of the optically thick disk with a range of radii ( 3.0-10.0 ) \times 10 ^ { 9 } cm .
The RXTE and optical ( RTT150 ) data of SS Cyg in outburst and quiescence reveal that the inner disk radius moves towards the white dwarf and receeds as the outburst declines to quiescence .
A preliminary analysis of SU UMa indicates a similar behaviour .
In addition , I find that the outburst spectra of WZ Sge shows two component spectrum of only hard X-ray emission , one of which may be fitted with a power law suggesting thermal Comptonization occuring in the system .
Cross-correlations between the simultaneous UV and X-ray light curves ( XMM - Newton ) of five DNe in quiescence show time lags in the X-rays of 96-181 sec consistent with travel time of matter from a truncated inner disk to the white dwarf surface .
All this suggests that dwarf novae and other plausible nonmagnetic systems have truncated accretion disks indicating that the disks may be partially evaporated and the accretion may occur through hot ( coronal ) flows in the disk .