diff --git a/libraries/gpu/src/gpu/GLBackend.h b/libraries/gpu/src/gpu/GLBackend.h
index 85fada4016..31adb84040 100644
--- a/libraries/gpu/src/gpu/GLBackend.h
+++ b/libraries/gpu/src/gpu/GLBackend.h
@@ -193,7 +193,7 @@ public:
 
 
     static const int MAX_NUM_ATTRIBUTES = Stream::NUM_INPUT_SLOTS;
-    static const int MAX_NUM_INPUT_BUFFERS = 16;
+    static const int MAX_NUM_INPUT_BUFFERS = Stream::NUM_INPUT_SLOTS;
 
     size_t getNumInputBuffers() const { return _input._invalidBuffers.size(); }
 
diff --git a/libraries/gpu/src/gpu/Stream.cpp b/libraries/gpu/src/gpu/Stream.cpp
index ff765f3250..9bb12862d8 100644
--- a/libraries/gpu/src/gpu/Stream.cpp
+++ b/libraries/gpu/src/gpu/Stream.cpp
@@ -38,10 +38,7 @@ const ElementArray& getDefaultElements() {
         //INSTANCE_SCALE = 8,
         Element::VEC3F_XYZ,
         //INSTANCE_TRANSLATE = 9,
-        Element::VEC3F_XYZ,
-        //INSTANCE_XFM = 10, 
-        // FIXME make a matrix element
-        Element::VEC4F_XYZW
+        Element::VEC3F_XYZ
     }};
     return defaultElements;
 }
diff --git a/libraries/gpu/src/gpu/Stream.h b/libraries/gpu/src/gpu/Stream.h
index 4214b99b74..f73eb1adbc 100644
--- a/libraries/gpu/src/gpu/Stream.h
+++ b/libraries/gpu/src/gpu/Stream.h
@@ -40,8 +40,9 @@ public:
         INSTANCE_SCALE = 8,
         INSTANCE_TRANSLATE = 9,
 
+
         DRAW_CALL_INFO = 15, // Reserve last input slot for draw call infos
-        NUM_INPUT_SLOTS = DRAW_CALL_INFO + 1,
+        NUM_INPUT_SLOTS = DRAW_CALL_INFO
     };
 
     typedef uint8 Slot;