  In this paper, we further develop a family of parallel time integrators known
as Revisionist Integral Deferred Correction methods (RIDC) to allow for the
semi-implicit solution of time dependent PDEs. Additionally, we show that our
semi-implicit RIDC algorithm can harness the computational potential of
multiple general purpose graphical processing units (GPUs) in a single node by
utilizing existing CUBLAS libraries for matrix linear algebra routines in our
implementation. In the numerical experiments, we show that our implementation
computes a fourth order solution using four GPUs and four CPUs in approximately
the same wall clock time as a first order solution computed using a single GPU
and a single CPU.
