diff --git a/docs/html/struct_vma_allocator_create_info.html b/docs/html/struct_vma_allocator_create_info.html
index 25fd89f..564e562 100644
--- a/docs/html/struct_vma_allocator_create_info.html
+++ b/docs/html/struct_vma_allocator_create_info.html
@@ -216,7 +216,7 @@ Public Attributes</h2></td></tr>
 <li>If user tries to allocate more memory from that heap using this allocator, the allocation fails with <code>VK_ERROR_OUT_OF_DEVICE_MEMORY</code>.</li>
 <li>If the limit is smaller than heap size reported in <code>VkMemoryHeap::size</code>, the value of this limit will be reported instead when using <a class="el" href="vk__mem__alloc_8h.html#ab88db292a17974f911182543fda52d19">vmaGetMemoryProperties()</a>.</li>
 </ul>
-<p>Warning! Using this feature may not be equivalent to installing a GPU with smaller amount of memory, because graphics driver doesn't necessary fail new allocations with <code>VK_ERROR_OUT_OF_DEVICE_MEMORY</code> result when memory capacity is exceeded. It may return success and just silently migrate some device memory blocks to system RAM. </p>
+<p>Warning! Using this feature may not be equivalent to installing a GPU with smaller amount of memory, because graphics driver doesn't necessary fail new allocations with <code>VK_ERROR_OUT_OF_DEVICE_MEMORY</code> result when memory capacity is exceeded. It may return success and just silently migrate some device memory blocks to system RAM. This driver behavior can also be controlled using VK_AMD_memory_overallocation_behavior extension. </p>
 
 </div>
 </div>
diff --git a/src/VmaUsage.h b/src/VmaUsage.h
index 43e1671..f785ba2 100644
--- a/src/VmaUsage.h
+++ b/src/VmaUsage.h
@@ -8,7 +8,8 @@
 #include <Windows.h>
 #define VK_USE_PLATFORM_WIN32_KHR
 
-#include <vulkan/vulkan.h>
+// Uncomment to test including `vulkan.h` on your own before including VMA.
+//#include <vulkan/vulkan.h>
 
 /*
 In every place where you want to use Vulkan Memory Allocator, define appropriate
diff --git a/src/vk_mem_alloc.h b/src/vk_mem_alloc.h
index f45a742..b50ed60 100644
--- a/src/vk_mem_alloc.h
+++ b/src/vk_mem_alloc.h
@@ -1493,7 +1493,9 @@ available through VmaAllocatorCreateInfo::pRecordSettings.
     #define NOMINMAX // For windows.h
 #endif
 
-#include <vulkan/vulkan.h>
+#ifndef VULKAN_H_
+    #include <vulkan/vulkan.h>
+#endif
 
 #if VMA_RECORDING_ENABLED
     #include <windows.h>
@@ -1690,7 +1692,8 @@ typedef struct VmaAllocatorCreateInfo
     smaller amount of memory, because graphics driver doesn't necessary fail new
     allocations with `VK_ERROR_OUT_OF_DEVICE_MEMORY` result when memory capacity is
     exceeded. It may return success and just silently migrate some device memory
-    blocks to system RAM.
+    blocks to system RAM. This driver behavior can also be controlled using
+    VK_AMD_memory_overallocation_behavior extension.
     */
     const VkDeviceSize* pHeapSizeLimit;
     /** \brief Pointers to Vulkan functions. Can be null if you leave define `VMA_STATIC_VULKAN_FUNCTIONS 1`.