diff --git a/CMakeLists.txt b/CMakeLists.txt
index 60543e1939a..b4272d5f118 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -110,7 +110,7 @@ OPTION(WITH_LZO           "Enable fast LZO compression (used for pointcache)" ON
 OPTION(WITH_LZMA          "Enable best LZMA compression, (used for pointcache)" ON)
 
 # Misc
-OPTION(WITH_RAYOPTIMIZATION	"Enable use of SIMD (SSE) optimizations for the raytracer" OFF) 
+OPTION(WITH_RAYOPTIMIZATION	"Enable use of SIMD (SSE) optimizations for the raytracer" ON) 
 OPTION(WITH_CXX_GUARDEDALLOC "Enable GuardedAlloc for C++ memory allocation tracking" OFF)
 OPTION(WITH_INSTALL       "Install accompanying scripts and language files needed to run blender" ON)
 
diff --git a/config/linux2-config.py b/config/linux2-config.py
index 199ea391d4e..213c20bd7d0 100644
--- a/config/linux2-config.py
+++ b/config/linux2-config.py
@@ -168,7 +168,7 @@ BF_EXPAT_LIBPATH = '/usr/lib'
 WITH_BF_OPENMP = True
 
 #Ray trace optimization
-WITH_BF_RAYOPTIMIZATION = False
+WITH_BF_RAYOPTIMIZATION = True
 BF_RAYOPTIMIZATION_SSE_FLAGS = ['-msse','-pthread']
 
 ##
diff --git a/config/linuxcross-config.py b/config/linuxcross-config.py
index 8533c8ac9c7..1650201f8c6 100644
--- a/config/linuxcross-config.py
+++ b/config/linuxcross-config.py
@@ -169,7 +169,7 @@ BF_OPENCOLLADA_LIB = 'OpenCOLLADAStreamWriter OpenCOLLADASaxFrameworkLoader Open
 BF_OPENCOLLADA_LIBPATH = '${BF_OPENCOLLADA}/lib ${BF_ICONV_LIBPATH}'
 
 #Ray trace optimization
-WITH_BF_RAYOPTIMIZATION = False
+WITH_BF_RAYOPTIMIZATION = True
 BF_RAYOPTIMIZATION_SSE_FLAGS = ['-msse']
 
 CCFLAGS = [ '-pipe', '-funsigned-char', '-fno-strict-aliasing' ]
diff --git a/config/win32-mingw-config.py b/config/win32-mingw-config.py
index f8b67781172..9d4c00e569b 100644
--- a/config/win32-mingw-config.py
+++ b/config/win32-mingw-config.py
@@ -155,7 +155,7 @@ BF_OPENCOLLADA_LIB = 'OpenCOLLADAStreamWriter OpenCOLLADASaxFrameworkLoader Open
 BF_OPENCOLLADA_LIBPATH = '${BF_OPENCOLLADA}/lib'
 
 #Ray trace optimization
-WITH_BF_RAYOPTIMIZATION = False
+WITH_BF_RAYOPTIMIZATION = True
 BF_RAYOPTIMIZATION_SSE_FLAGS = ['-msse']
 
 ##
diff --git a/config/win32-vc-config.py b/config/win32-vc-config.py
index 02bce0cc7f3..ce34737fd49 100644
--- a/config/win32-vc-config.py
+++ b/config/win32-vc-config.py
@@ -150,7 +150,7 @@ BF_OPENCOLLADA_LIB = 'OpenCOLLADAStreamWriter OpenCOLLADASaxFrameworkLoader Open
 BF_OPENCOLLADA_LIBPATH = '${BF_OPENCOLLADA}/lib'
 
 #Ray trace optimization
-WITH_BF_RAYOPTIMIZATION = False
+WITH_BF_RAYOPTIMIZATION = True
 BF_RAYOPTIMIZATION_SSE_FLAGS = ['/arch:SSE']
 
 WITH_BF_STATICOPENGL = False
diff --git a/config/win64-vc-config.py b/config/win64-vc-config.py
index de1daa16e0b..46b9034823c 100644
--- a/config/win64-vc-config.py
+++ b/config/win64-vc-config.py
@@ -163,7 +163,7 @@ BF_OPENCOLLADA_LIB = 'OpenCOLLADAStreamWriter OpenCOLLADASaxFrameworkLoader Open
 BF_OPENCOLLADA_LIBPATH = '${BF_OPENCOLLADA}/lib'
 
 #Ray trace optimization
-WITH_BF_RAYOPTIMIZATION = False
+WITH_BF_RAYOPTIMIZATION = True
 BF_RAYOPTIMIZATION_SSE_FLAGS = ['/arch:SSE','/arch:SSE2']
 
 WITH_BF_STATICOPENGL = False
diff --git a/source/blender/blenlib/BLI_cpu.h b/source/blender/blenlib/BLI_cpu.h
new file mode 100644
index 00000000000..d809f1cc594
--- /dev/null
+++ b/source/blender/blenlib/BLI_cpu.h
@@ -0,0 +1,30 @@
+/*
+ *
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#ifndef BLI_CPU_H
+#define BLI_CPU_H 
+
+int BLI_cpu_support_sse2(void);
+
+#endif
+
diff --git a/source/blender/blenlib/intern/cpu.c b/source/blender/blenlib/intern/cpu.c
new file mode 100644
index 00000000000..490e1c3f02a
--- /dev/null
+++ b/source/blender/blenlib/intern/cpu.c
@@ -0,0 +1,52 @@
+/**
+ *
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version. 
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#include "BLI_cpu.h"
+
+int BLI_cpu_support_sse2(void)
+{
+#if defined(__x86_64__) || defined(_M_X64)
+	/* x86_64 always has SSE2 instructions */
+	return 1;
+#elif defined(__GNUC__) && defined(i386)
+	/* for GCC x86 we check cpuid */
+	unsigned int a, b, c, d;
+	__asm__("cpuid": "=a"(a), "=b"(b), "=c"(c), "=d"(d): "a"(1));
+	return (d & 0x04000000) != 0;
+#elif (defined(_MSC_VER) && defined(_M_IX86))
+	/* also check cpuid for MSVC x86 */
+	unsigned int d;
+	__asm {
+		xor     eax, eax
+		inc     eax
+		push    ebx
+		cpuid
+		pop     ebx
+		mov     d, edx
+	}
+	return (d & 0x04000000) != 0;
+#endif
+
+	return 0;
+}
+
diff --git a/source/blender/render/intern/source/rayshade.c b/source/blender/render/intern/source/rayshade.c
index bd6e804f13b..bdc1dcc2782 100644
--- a/source/blender/render/intern/source/rayshade.c
+++ b/source/blender/render/intern/source/rayshade.c
@@ -41,9 +41,10 @@
 #include "BKE_node.h"
 #include "BKE_utildefines.h"
 
-#include "BLI_math.h"
 #include "BLI_blenlib.h"
+#include "BLI_cpu.h"
 #include "BLI_jitter.h"
+#include "BLI_math.h"
 #include "BLI_rand.h"
 
 #include "PIL_time.h"
@@ -98,7 +99,7 @@ RayObject*  RE_rayobject_create(Render *re, int type, int size)
 		//TODO
 		//if(detect_simd())
 #ifdef __SSE__
-		type = R_RAYSTRUCTURE_SIMD_SVBVH;
+		type = BLI_cpu_support_sse2()? R_RAYSTRUCTURE_SIMD_SVBVH: R_RAYSTRUCTURE_VBVH;
 #else
 		type = R_RAYSTRUCTURE_VBVH;
 #endif