diff --git a/common/sys/sysinfo.cpp b/common/sys/sysinfo.cpp
index 2a6dfed483..3cac370276 100644
--- a/common/sys/sysinfo.cpp
+++ b/common/sys/sysinfo.cpp
@@ -99,6 +99,9 @@ namespace embree
 
   CPUModel getCPUModel() 
   {
+    if (getCPUVendor() != "GenuineIntel")
+      return CPU_UNKNOWN;
+    
     int out[4];
     __cpuid(out, 0);
     if (out[0] < 1) return CPU_UNKNOWN;
@@ -119,6 +122,7 @@ namespace embree
     if (model == 0x2D) return CPU_CORE_SANDYBRIDGE;  // Core i7, SandyBridge
     if (model == 0x45) return CPU_HASWELL;           // Haswell
     if (model == 0x3C) return CPU_HASWELL;           // Haswell
+    if (model == 0x55) return CPU_SKYLAKE_SERVER;   // Skylake server based CPUs
     return CPU_UNKNOWN;
   }
 
@@ -131,7 +135,7 @@ namespace embree
     case CPU_CORE_SANDYBRIDGE: return "SandyBridge";
     case CPU_HASWELL         : return "Haswell";
     case CPU_KNIGHTS_LANDING : return "Knights Landing";
-    case CPU_SKYLAKE         : return "Skylake";
+    case CPU_SKYLAKE_SERVER  : return "Skylake Server";
     default                  : return "Unknown CPU";
     }
   }
@@ -242,7 +246,7 @@ namespace embree
     if (xmm_enabled && cpuid_leaf_1[ECX] & CPU_FEATURE_BIT_SSE4_1) cpu_features |= CPU_FEATURE_SSE41;
     if (xmm_enabled && cpuid_leaf_1[ECX] & CPU_FEATURE_BIT_SSE4_2) cpu_features |= CPU_FEATURE_SSE42;
     if (               cpuid_leaf_1[ECX] & CPU_FEATURE_BIT_POPCNT) cpu_features |= CPU_FEATURE_POPCNT;
-    if (ymm_enabled && cpuid_leaf_1[ECX] & CPU_FEATURE_BIT_AVX   ) cpu_features |= CPU_FEATURE_AVX;
+    if (ymm_enabled && cpuid_leaf_1[ECX] & CPU_FEATURE_BIT_AVX   ) cpu_features |= CPU_FEATURE_AVX | CPU_FEATURE_PSEUDO_HIFREQ256BIT;
     if (xmm_enabled && cpuid_leaf_1[ECX] & CPU_FEATURE_BIT_F16C  ) cpu_features |= CPU_FEATURE_F16C;
     if (               cpuid_leaf_1[ECX] & CPU_FEATURE_BIT_RDRAND) cpu_features |= CPU_FEATURE_RDRAND;
     if (ymm_enabled && cpuid_leaf_7[EBX] & CPU_FEATURE_BIT_AVX2  ) cpu_features |= CPU_FEATURE_AVX2;
@@ -261,6 +265,9 @@ namespace embree
     if (zmm_enabled && cpuid_leaf_7[EBX] & CPU_FEATURE_BIT_AVX512VL  ) cpu_features |= CPU_FEATURE_AVX512VL;
     if (zmm_enabled && cpuid_leaf_7[ECX] & CPU_FEATURE_BIT_AVX512VBMI) cpu_features |= CPU_FEATURE_AVX512VBMI;
 
+    if (getCPUModel() == CPU_SKYLAKE_SERVER)
+      cpu_features &= ~CPU_FEATURE_PSEUDO_HIFREQ256BIT;
+
     return cpu_features;
   }
 
diff --git a/common/sys/sysinfo.h b/common/sys/sysinfo.h
index 8f562fcb59..bce6f62138 100644
--- a/common/sys/sysinfo.h
+++ b/common/sys/sysinfo.h
@@ -86,7 +86,7 @@ namespace embree
     CPU_CORE_SANDYBRIDGE,
     CPU_HASWELL,
     CPU_KNIGHTS_LANDING,
-    CPU_SKYLAKE
+    CPU_SKYLAKE_SERVER
   };
 
   /*! get the full path to the running executable */
@@ -133,6 +133,8 @@ namespace embree
   static const int CPU_FEATURE_AVX512IFMA = 1 << 23;
   static const int CPU_FEATURE_AVX512VBMI = 1 << 24;
  
+  static const int CPU_FEATURE_PSEUDO_HIFREQ256BIT = 1 << 30;
+ 
   /*! get CPU features */
   int getCPUFeatures();
 
@@ -155,6 +157,9 @@ namespace embree
   static const int AVX512KNL = AVX2 | CPU_FEATURE_AVX512F | CPU_FEATURE_AVX512PF | CPU_FEATURE_AVX512ER | CPU_FEATURE_AVX512CD;
   static const int AVX512SKX = AVX2 | CPU_FEATURE_AVX512F | CPU_FEATURE_AVX512DQ | CPU_FEATURE_AVX512CD | CPU_FEATURE_AVX512BW | CPU_FEATURE_AVX512VL;
 
+  static const int AVX_FAST = AVX | CPU_FEATURE_PSEUDO_HIFREQ256BIT;
+  static const int AVX2_FAST = AVX2 | CPU_FEATURE_PSEUDO_HIFREQ256BIT;
+
   /*! converts ISA bitvector into a string */
   std::string stringOfISA(int features);
 
diff --git a/kernels/common/scene.cpp b/kernels/common/scene.cpp
index 22ed0c9fee..eec731cffd 100644
--- a/kernels/common/scene.cpp
+++ b/kernels/common/scene.cpp
@@ -153,7 +153,7 @@ namespace embree
         switch (mode) {
         case /*0b00*/ 0: 
 #if defined (EMBREE_TARGET_SIMD8)
-          if (device->hasISA(AVX))
+          if (device->hasISA(AVX_FAST))
 	  {
             if (isHighQuality()) 
               accels.add(device->bvh8_factory->BVH8Triangle4(this,BVHFactory::BuildVariant::HIGH_QUALITY,BVHFactory::IntersectVariant::FAST));
@@ -172,7 +172,7 @@ namespace embree
 
         case /*0b01*/ 1: 
 #if defined (EMBREE_TARGET_SIMD8)
-          if (device->hasISA(AVX)) 
+          if (device->hasISA(AVX_FAST)) 
             accels.add(device->bvh8_factory->BVH8Triangle4v(this,BVHFactory::BuildVariant::STATIC,BVHFactory::IntersectVariant::ROBUST));
           else
 #endif
@@ -186,7 +186,7 @@ namespace embree
       else /* dynamic */
       {
 #if defined (EMBREE_TARGET_SIMD8)
-          if (device->hasISA(AVX))
+          if (device->hasISA(AVX_FAST))
 	  {
             int mode =  2*(int)isCompact() + 1*(int)isRobust();
             switch (mode) {
@@ -233,7 +233,7 @@ namespace embree
       int mode =  2*(int)isCompact() + 1*(int)isRobust(); 
       
 #if defined (EMBREE_TARGET_SIMD8)
-      if (device->hasISA(AVX2)) // BVH8 reduces performance on AVX only-machines
+      if (device->hasISA(AVX2_FAST)) // BVH8 reduces performance on AVX only-machines
       {
         switch (mode) {
         case /*0b00*/ 0: accels.add(device->bvh8_factory->BVH8Triangle4iMB(this,BVHFactory::BuildVariant::STATIC,BVHFactory::IntersectVariant::FAST  )); break;
@@ -275,7 +275,7 @@ namespace embree
         switch (mode) {
         case /*0b00*/ 0:
 #if defined (EMBREE_TARGET_SIMD8)
-          if (device->hasISA(AVX))
+          if (device->hasISA(AVX_FAST))
           {
             if (isHighQuality()) 
               accels.add(device->bvh8_factory->BVH8Quad4v(this,BVHFactory::BuildVariant::HIGH_QUALITY,BVHFactory::IntersectVariant::FAST));
@@ -294,7 +294,7 @@ namespace embree
 
         case /*0b01*/ 1:
 #if defined (EMBREE_TARGET_SIMD8)
-          if (device->hasISA(AVX))
+          if (device->hasISA(AVX_FAST))
             accels.add(device->bvh8_factory->BVH8Quad4v(this,BVHFactory::BuildVariant::STATIC,BVHFactory::IntersectVariant::ROBUST));
           else
 #endif
@@ -308,7 +308,7 @@ namespace embree
       else /* dynamic */
       {
 #if defined (EMBREE_TARGET_SIMD8)
-          if (device->hasISA(AVX))
+          if (device->hasISA(AVX_FAST))
 	  {
             int mode =  2*(int)isCompact() + 1*(int)isRobust();
             switch (mode) {
@@ -353,7 +353,7 @@ namespace embree
       switch (mode) {
       case /*0b00*/ 0:
 #if defined (EMBREE_TARGET_SIMD8)
-        if (device->hasISA(AVX))
+        if (device->hasISA(AVX_FAST))
           accels.add(device->bvh8_factory->BVH8Quad4iMB(this,BVHFactory::BuildVariant::STATIC,BVHFactory::IntersectVariant::FAST));
         else
 #endif
@@ -362,7 +362,7 @@ namespace embree
 
       case /*0b01*/ 1:
 #if defined (EMBREE_TARGET_SIMD8)
-        if (device->hasISA(AVX))
+        if (device->hasISA(AVX_FAST))
           accels.add(device->bvh8_factory->BVH8Quad4iMB(this,BVHFactory::BuildVariant::STATIC,BVHFactory::IntersectVariant::ROBUST));
         else
 #endif
@@ -390,7 +390,7 @@ namespace embree
       if (isStatic())
       {
 #if defined (EMBREE_TARGET_SIMD8)
-        if (device->hasISA(AVX2)) // only enable on HSW machines, for SNB this codepath is slower
+        if (device->hasISA(AVX2_FAST)) // only enable on HSW machines, for SNB this codepath is slower
         {
           switch (mode) {
           case /*0b00*/ 0: accels.add(device->bvh8_factory->BVH8OBBBezier1v(this)); break;
@@ -438,7 +438,7 @@ namespace embree
     if (device->hair_accel_mb == "default")
     {
 #if defined (EMBREE_TARGET_SIMD8)
-      if (device->hasISA(AVX2) && !isCompact()) // only enable on HSW machines, on SNB this codepath is slower
+      if (device->hasISA(AVX2_FAST) && !isCompact()) // only enable on HSW machines, on SNB this codepath is slower
       {
         accels.add(device->bvh8_factory->BVH8OBBBezier1iMB(this));
       }
@@ -464,7 +464,7 @@ namespace embree
       if (isStatic())
       {
 #if defined (EMBREE_TARGET_SIMD8)
-        if (device->hasISA(AVX) && !isCompact())
+        if (device->hasISA(AVX_FAST) && !isCompact())
           accels.add(device->bvh8_factory->BVH8Line4i(this));
         else
 #endif
@@ -489,7 +489,7 @@ namespace embree
     if (device->line_accel_mb == "default")
     {
 #if defined (EMBREE_TARGET_SIMD8)
-      if (device->hasISA(AVX) && !isCompact())
+      if (device->hasISA(AVX_FAST) && !isCompact())
         accels.add(device->bvh8_factory->BVH8Line4iMB(this));
       else
 #endif
@@ -543,7 +543,7 @@ namespace embree
     if (device->object_accel == "default") 
     {
 #if defined (EMBREE_TARGET_SIMD8)
-      if (device->hasISA(AVX) && !isCompact())
+      if (device->hasISA(AVX_FAST) && !isCompact())
       {
         //if (isStatic()) {
         accels.add(device->bvh8_factory->BVH8UserGeometry(this,BVHFactory::BuildVariant::STATIC));
@@ -574,7 +574,7 @@ namespace embree
 #if defined(EMBREE_GEOMETRY_USER)
     if (device->object_accel_mb == "default"    ) {
 #if defined (EMBREE_TARGET_SIMD8)
-      if (device->hasISA(AVX) && !isCompact())
+      if (device->hasISA(AVX_FAST) && !isCompact())
         accels.add(device->bvh8_factory->BVH8UserGeometryMB(this));
       else
 #endif