The growing power of central processing units (CPU) has made it possible to use quantum mechanical (QM)
calculations for in silico drug discovery. However, limited CPU power makes large-scale in silico screening such as
virtual screening with QM calculations a challenge. Recently, general-purpose computing on graphics processing units
(GPGPU) has offered an alternative, because of its significantly accelerated computational time over CPU. Here, we
review a GPGPU-based supercomputer, TSUBAME2.0, and its promise for next generation in silico drug discovery, in
high-density (HD) silico drug discovery.