diff --git a/Source/gs/GsCachedAreaTest.cpp b/Source/gs/GsCachedAreaTest.cpp
new file mode 100644
index 00000000..e7be48ec
--- /dev/null
+++ b/Source/gs/GsCachedAreaTest.cpp
@@ -0,0 +1,156 @@
+#include "GsCachedAreaTest.h"
+#include "GsCachedArea.h"
+#include "GSHandler.h"
+#include "GsPixelFormats.h"
+
+void CGsCachedAreaTest::Execute()
+{
+	CheckEmptyArea();
+	CheckDirtyRect();
+	CheckClearDirtyPages();
+	CheckInvalidate();
+}
+
+void CGsCachedAreaTest::CheckEmptyArea()
+{
+	CGsCachedArea area;
+	area.SetArea(CGSHandler::PSMCT32, 0, 0, 0);
+
+	auto areaRect = area.GetAreaPageRect();
+	assert(areaRect.width == 0);
+	assert(areaRect.height == 0);
+
+	auto areaSize = area.GetSize();
+	assert(areaSize == 0);
+
+	auto dirtyRect = area.GetDirtyPageRect();
+	assert(dirtyRect.x == 0);
+	assert(dirtyRect.y == 0);
+	assert(dirtyRect.width == 0);
+	assert(dirtyRect.height == 0);
+}
+
+void CGsCachedAreaTest::CheckDirtyRect()
+{
+	//Completely dirty
+	{
+		CGsCachedArea area;
+		area.SetArea(CGSHandler::PSMCT32, 0, 512, 512);
+
+		auto areaRect = area.GetAreaPageRect();
+		for(uint32 y = 0; y < areaRect.height; y++)
+		{
+			for(uint32 x = 0; x < areaRect.width; x++)
+			{
+				uint32 pageIndex = x + (y * areaRect.width);
+				area.SetPageDirty(pageIndex);
+			}
+		}
+
+		auto dirtyRect = area.GetDirtyPageRect();
+		assert(dirtyRect.x == 0);
+		assert(dirtyRect.y == 0);
+		assert(dirtyRect.width == areaRect.width);
+		assert(dirtyRect.height == areaRect.height);
+	}
+
+	//One page
+	{
+		CGsCachedArea area;
+		area.SetArea(CGSHandler::PSMCT32, 0, 512, 512);
+
+		auto areaRect = area.GetAreaPageRect();
+		uint32 dirtyX = 3;
+		uint32 dirtyY = 2;
+		area.SetPageDirty(dirtyX + (dirtyY * areaRect.width));
+
+		auto dirtyRect = area.GetDirtyPageRect();
+		assert(dirtyRect.x == dirtyX);
+		assert(dirtyRect.y == dirtyY);
+		assert(dirtyRect.width == 1);
+		assert(dirtyRect.height == 1);
+	}
+
+	//Completely clear
+	{
+		CGsCachedArea area;
+		area.SetArea(CGSHandler::PSMCT32, 0, 512, 512);
+
+		auto dirtyRect = area.GetDirtyPageRect();
+		assert(dirtyRect.x == 0);
+		assert(dirtyRect.y == 0);
+		assert(dirtyRect.width == 0);
+		assert(dirtyRect.height == 0);
+	}
+}
+
+void CGsCachedAreaTest::CheckClearDirtyPages()
+{
+	CGsCachedArea area;
+	area.SetArea(CGSHandler::PSMCT32, 0, 512, 512);
+
+	auto areaRect = area.GetAreaPageRect();
+	uint32 dirtyX = 3;
+	uint32 dirtyY = 2;
+	area.SetPageDirty(dirtyX + (dirtyY * areaRect.width));
+	assert(area.HasDirtyPages());
+
+	area.ClearDirtyPages(CGsCachedArea::PageRect { 0, 0, 1, 1 });
+	assert(area.HasDirtyPages());
+
+	area.ClearDirtyPages(CGsCachedArea::PageRect { 0, 0, 3, 2 });
+	assert(area.HasDirtyPages());
+
+	area.ClearDirtyPages(CGsCachedArea::PageRect { 3, 2, 1, 1 });
+	assert(!area.HasDirtyPages());
+}
+
+void CGsCachedAreaTest::CheckInvalidate()
+{
+	auto pixelFormat = CGSHandler::PSMCT32;
+	auto pageSize = CGsPixelFormats::GetPsmPageSize(pixelFormat);
+	uint32 areaWidth = 512;
+	uint32 areaPageWidth = areaWidth / pageSize.first;
+
+	//Invalidate first line
+	{
+		CGsCachedArea area;
+		area.SetArea(pixelFormat, 0, areaWidth, 512);
+
+		area.Invalidate(0, areaPageWidth * CGsPixelFormats::PAGESIZE);
+
+		auto dirtyRect = area.GetDirtyPageRect();
+		assert(dirtyRect.x == 0);
+		assert(dirtyRect.y == 0);
+		assert(dirtyRect.width == areaPageWidth);
+		assert(dirtyRect.height == 1);
+	}
+
+	//Invalidate second line
+	{
+		CGsCachedArea area;
+		area.SetArea(pixelFormat, 0, areaWidth, 512);
+
+		area.Invalidate(areaPageWidth * CGsPixelFormats::PAGESIZE, areaPageWidth * CGsPixelFormats::PAGESIZE);
+
+		auto dirtyRect = area.GetDirtyPageRect();
+		assert(dirtyRect.x == 0);
+		assert(dirtyRect.y == 1);
+		assert(dirtyRect.width == areaPageWidth);
+		assert(dirtyRect.height == 1);
+	}
+
+	//Invalidate two first lines
+	{
+		CGsCachedArea area;
+		area.SetArea(pixelFormat, 0, areaWidth, 512);
+
+		area.Invalidate(0, areaPageWidth * CGsPixelFormats::PAGESIZE * 2);
+
+		auto dirtyRect = area.GetDirtyPageRect();
+		assert(dirtyRect.x == 0);
+		assert(dirtyRect.y == 0);
+		assert(dirtyRect.width == areaPageWidth);
+		assert(dirtyRect.height == 2);
+	}
+}
diff --git a/Source/gs/GsCachedAreaTest.h b/Source/gs/GsCachedAreaTest.h
new file mode 100644
index 00000000..18fe83d6
--- /dev/null
+++ b/Source/gs/GsCachedAreaTest.h
@@ -0,0 +1,13 @@
+#pragma once
+
+class CGsCachedAreaTest
+{
+public:
+	void Execute();
+
+private:
+	void CheckEmptyArea();
+	void CheckDirtyRect();
+	void CheckClearDirtyPages();
+	void CheckInvalidate();
+};