diff --git a/var/spack/repos/builtin/packages/cuda/package.py b/var/spack/repos/builtin/packages/cuda/package.py
index eca371d05a..ea083d8651 100644
--- a/var/spack/repos/builtin/packages/cuda/package.py
+++ b/var/spack/repos/builtin/packages/cuda/package.py
@@ -13,7 +13,11 @@ class Cuda(Package):
     For the Installer Type, select runfile and click Download. Spack will search
     your current directory for this file. Alternatively, add this file to a
     mirror so that Spack can find it. For instructions on how to set up a mirror,
-    see http://software.llnl.gov/spack/mirrors.html"""
+    see http://software.llnl.gov/spack/mirrors.html
+
+    Note: This package does not currently install the drivers necessary to run
+    CUDA. These will need to be installed manually. See:
+    http://docs.nvidia.com/cuda/cuda-getting-started-guide-for-linux for details."""
 
     homepage = "http://www.nvidia.com/object/cuda_home_new.html"
 
diff --git a/var/spack/repos/builtin/packages/hoomd-blue/package.py b/var/spack/repos/builtin/packages/hoomd-blue/package.py
index 32fdff9426..d310b7687a 100644
--- a/var/spack/repos/builtin/packages/hoomd-blue/package.py
+++ b/var/spack/repos/builtin/packages/hoomd-blue/package.py
@@ -16,9 +16,9 @@ class HoomdBlue(Package):
 
     version('1.3.3', '1469ef4531dc14b579c0acddbfe6a273')
 
-    variant('mpi',  default=False, description='Compile with MPI enabled')
-    variant('cuda', default=False, description='Compile with CUDA Toolkit')
-    variant('doc',  default=False, description='Generate documentation')
+    variant('mpi',  default=True, description='Compile with MPI enabled')
+    variant('cuda', default=True, description='Compile with CUDA Toolkit')
+    variant('doc',  default=True, description='Generate documentation')
 
     extends('python')
     depends_on('py-numpy')
@@ -56,6 +56,7 @@ def install(self, spec, prefix):
 
         # There may be a bug in the MPI-CUDA code. See:
         # https://groups.google.com/forum/#!msg/hoomd-users/2griTESmc5I/E69s_M5fDwAJ
+        # This prevented "make test" from passing for me.
         cmake_args.append('-DENABLE_MPI_CUDA=OFF')
 
         # Documentation