  We accelerated an {\it ab-initio} QMC electronic structure calculation by
using GPGPU. The bottleneck of the calculation for extended solid systems is
replaced by CUDA-GPGPU subroutine kernels which build up spline basis set
expansions of electronic orbital functions at each Monte Carlo step. We
achieved 30.8 times faster evaluation for the bottleneck, confirmed on the
simulation of TiO$_2$ solid with 1,536 electrons. To achieve better performance
in GPGPU we propose a new updating scheme for Monte Carlo sampling,
quasi-simultaneous updating, which is in between the
configuration-by-configuration updating and the widely-used
particle-by-particle one. The energy deviation caused both by the single
precision treatment and the new updating scheme is found to be within the
accuracy required in the calculation, $\sim 10^{-3}$ hartree per primitive
cell.
