diff --git a/Makefile b/Makefile
index 2fcb3f9..4eda78b 100644
--- a/Makefile
+++ b/Makefile
@@ -10,6 +10,7 @@ IMAGES = common \
 		gpu/rectangles \
 		gpu/texture-overflow \
 		gpu/mask-bit \
+		gpu/gp0-e1 \
 		gte-fuzz \
 		spu/test \
 		spu/stereo \
diff --git a/README.md b/README.md
index 61f9101..dd7c9dc 100644
--- a/README.md
+++ b/README.md
@@ -15,6 +15,7 @@ gpu/lines            | Draws lines using different modes - for verifying Bresenh
 gpu/rectangles       | Draws all combinations of Rectangle commands
 gpu/texture-overflow | Draws textured rectangle with UV overflowing VRAM width
 gpu/mask-bit         | Check Mask bit behavior during VRAM copy operations
+gpu/gp0-e1           | Check if GP0_E1, GPUSTAT and polygon render uses the same register internally
 gte-fuzz             | Executes GTE opcodes with random parameters, can be used to verify against real console
 spu/test             | Check SPU behavior (data is lost randomly on 32bit access, ok on 16bit)
 spu/stereo           | Play samples on first two voices 
diff --git a/gpu/gp0-e1/Makefile b/gpu/gp0-e1/Makefile
new file mode 100644
index 0000000..1a1c545
--- /dev/null
+++ b/gpu/gp0-e1/Makefile
@@ -0,0 +1,3 @@
+include ../../common-test.mk
+
+TARGET = gp0-e1.elf
\ No newline at end of file
diff --git a/gpu/gp0-e1/main.cpp b/gpu/gp0-e1/main.cpp
new file mode 100644
index 0000000..032cbfc
--- /dev/null
+++ b/gpu/gp0-e1/main.cpp
@@ -0,0 +1,108 @@
+#include <common.h>
+#include <test.h>
+
+const uint32_t E1_MASK = 0b10000111'11111111;
+
+void drawTexturedPolygon(uint16_t texpage) {
+    POLY_FT4 p = {0};
+    setPolyFT4(&p);
+    setRGB0(&p, 0x80, 0x80, 0x80);
+    setClut(&p, 0, 0);
+    setUVWH(&p, 0, 0,255, 255);
+    setXY4(&p, 
+        0, 0,
+        0, 32,
+        32, 0,
+        32, 32
+    );
+    p.tpage = texpage; 
+    
+    DrawPrim(&p);
+}
+
+// Check if writing zeroes to GP0_E1 == what GPSTAT read
+void testWriteZerosToE1() {
+    writeGP1(0x09, 0); // Disable E1.11 bit
+    writeGP0(0xe1,0x000);
+    gpuNop();
+    
+    assertEquals((ReadGPUstat() & E1_MASK), 0b00000000'00000000);
+}
+
+// Check if writing ones to GP0_E1 == what GPSTAT read (no "Texture Disable")
+void testWriteOnesToE1() {
+    writeGP1(0x09, 0); // Disable E1.11 bit
+    writeGP0(0xe1, 0xfff);
+    gpuNop();
+
+    assertEquals((ReadGPUstat() & E1_MASK), 0b00000111'11111111);
+}
+
+// Check if writing ones to GP0_E1 == what GPSTAT read (with "Texture Disable")
+void testWriteOnesToE1WithTextureDisable() {
+    writeGP1(0x09, 1); // Enable E1.11 bit
+    writeGP0(0xe1,0xfff);
+    gpuNop();
+
+    assertEquals((ReadGPUstat() & E1_MASK), 0b10000111'11111111);
+}
+
+// Check which bits in GP0_E1 are changed by Textured Polygon draw commands
+//        vv - These two bits can be set via GP0_E1, but not via draw command
+// 0b10000111'11111111
+void testTexturedPolygons() {
+    writeGP1(0x09, 0); // Disable E1.11 bit
+    writeGP0(0xe1,0x000);
+    
+    drawTexturedPolygon(0xffff); 
+    gpuNop();
+
+    assertEquals((ReadGPUstat() & E1_MASK), 0b0000001'11111111);
+}
+
+// Check which bits in GP0_E1 are changed by Textured Polygon draw commands (Texture Disable allowed)
+void testTexturedPolygonsTextureDisable() {
+    writeGP1(0x09, 1); // Enable E1.11 bit
+    writeGP0(0xe1,0x000);
+
+    drawTexturedPolygon(0xffff); 
+    gpuNop();
+
+    assertEquals((ReadGPUstat() & E1_MASK), 0b10000001'11111111);
+}
+
+// Check if drawing textured polygons doesn't change other bits in E1 register
+void testTexturedPolygonsDoesNotChangeOtherBits() {
+    writeGP1(0x09, 1); // Enable E1.11 bit
+    writeGP0(0xe1,0xfff);
+
+    drawTexturedPolygon(0x0000); 
+    gpuNop();
+
+    assertEquals((ReadGPUstat() & E1_MASK), 0b00000110'00000000);
+}
+
+void runTests() {
+    testWriteZerosToE1();
+    testWriteOnesToE1();
+    testWriteOnesToE1WithTextureDisable();
+    testTexturedPolygons();
+    testTexturedPolygonsTextureDisable();
+    testTexturedPolygonsDoesNotChangeOtherBits();
+    
+    printf("Done.\n");
+}
+
+int main() {
+    initVideo(320, 240);
+    printf("\ngpu/gp0-e1\n");
+
+    clearScreen();
+
+    runTests();
+    
+    for (;;) {
+        VSync(0);
+    }
+    return 0;
+}
diff --git a/gpu/gp0-e1/psx.log b/gpu/gp0-e1/psx.log
new file mode 100644
index 0000000..b2c591f
--- /dev/null
+++ b/gpu/gp0-e1/psx.log
@@ -0,0 +1,8 @@
+gpu/gp0-e1
+pass - testWriteZerosToE1
+pass - testWriteOnesToE1
+pass - testWriteOnesToE1WithTextureDisable
+pass - testTexturedPolygons
+pass - testTexturedPolygonsTextureDisable
+pass - testTexturedPolygonsDoesNotChangeOtherBits
+Done.
\ No newline at end of file