diff --git a/util/test/demos/d3d12/d3d12_cbuffer_zoo.cpp b/util/test/demos/d3d12/d3d12_cbuffer_zoo.cpp
index cd6c421a8..5d43b48b7 100644
--- a/util/test/demos/d3d12/d3d12_cbuffer_zoo.cpp
+++ b/util/test/demos/d3d12/d3d12_cbuffer_zoo.cpp
@@ -300,10 +300,16 @@ float4 main() : SV_Target0
     ID3DBlobPtr vsblob = Compile(D3DDefaultVertex, "main", "vs_5_0");
     ID3DBlobPtr psblob = Compile(pixel, "main", "ps_5_1");
 
-    Vec4f cbufferdata[512];
+    const size_t bindOffset = 16;
+
+    Vec4f cbufferdata[bindOffset + 512];
+
+    for(int i = 0; i < bindOffset; i++)
+      cbufferdata[i] = Vec4f(-99.9f, -88.8f, -77.7f, -66.6f);
 
     for(int i = 0; i < 512; i++)
-      cbufferdata[i] = Vec4f(float(i * 4 + 0), float(i * 4 + 1), float(i * 4 + 2), float(i * 4 + 3));
+      cbufferdata[bindOffset + i] =
+          Vec4f(float(i * 4 + 0), float(i * 4 + 1), float(i * 4 + 2), float(i * 4 + 3));
 
     RootData rootData = {};
 
@@ -366,9 +372,11 @@ float4 main() : SV_Target0
       IASetVertexBuffer(cmd, vb, sizeof(DefaultA2V), 0);
       cmd->SetPipelineState(pso);
       cmd->SetGraphicsRootSignature(sig);
-      cmd->SetGraphicsRootConstantBufferView(0, cb->GetGPUVirtualAddress());
+      cmd->SetGraphicsRootConstantBufferView(
+          0, cb->GetGPUVirtualAddress() + bindOffset * sizeof(Vec4f));
       cmd->SetGraphicsRoot32BitConstants(1, sizeof(rootData) / sizeof(uint32_t), &rootData, 0);
-      cmd->SetGraphicsRootConstantBufferView(2, cb->GetGPUVirtualAddress() + 256);
+      cmd->SetGraphicsRootConstantBufferView(
+          2, cb->GetGPUVirtualAddress() + bindOffset * sizeof(Vec4f) + 256);
 
       RSSetViewport(cmd, {0.0f, 0.0f, (float)screenWidth, (float)screenHeight, 0.0f, 1.0f});
       RSSetScissorRect(cmd, {0, 0, screenWidth, screenHeight});
diff --git a/util/test/demos/gl/gl_cbuffer_zoo.cpp b/util/test/demos/gl/gl_cbuffer_zoo.cpp
index da2f7e76a..53fba7272 100644
--- a/util/test/demos/gl/gl_cbuffer_zoo.cpp
+++ b/util/test/demos/gl/gl_cbuffer_zoo.cpp
@@ -360,10 +360,16 @@ void main()
 
     GLuint program = MakeProgram(common + vertex, common + pixel);
 
-    Vec4f cbufferdata[1024];
+    const size_t bindOffset = 16;
+
+    Vec4f cbufferdata[1024 + bindOffset];
+
+    for(int i = 0; i < bindOffset; i++)
+      cbufferdata[i] = Vec4f(-99.9f, -88.8f, -77.7f, -66.6f);
 
     for(int i = 0; i < 1024; i++)
-      cbufferdata[i] = Vec4f(float(i * 4 + 0), float(i * 4 + 1), float(i * 4 + 2), float(i * 4 + 3));
+      cbufferdata[bindOffset + i] =
+          Vec4f(float(i * 4 + 0), float(i * 4 + 1), float(i * 4 + 2), float(i * 4 + 3));
 
     GLuint cb = MakeBuffer();
     glBindBuffer(GL_UNIFORM_BUFFER, cb);
@@ -389,7 +395,7 @@ void main()
       glBindFramebuffer(GL_FRAMEBUFFER, fbo);
       glBindVertexArray(vao);
 
-      glBindBufferBase(GL_UNIFORM_BUFFER, 0, cb);
+      glBindBufferRange(GL_UNIFORM_BUFFER, 0, cb, bindOffset * sizeof(Vec4f), 1024 * sizeof(Vec4f));
 
       glUseProgram(program);
 
diff --git a/util/test/demos/vk/vk_cbuffer_zoo.cpp b/util/test/demos/vk/vk_cbuffer_zoo.cpp
index 6b1556f9b..df84ed381 100644
--- a/util/test/demos/vk/vk_cbuffer_zoo.cpp
+++ b/util/test/demos/vk/vk_cbuffer_zoo.cpp
@@ -622,10 +622,16 @@ float4 main() : SV_Target0
 
     vb.upload(DefaultTri);
 
-    Vec4f cbufferdata[512];
+    const size_t bindOffset = 16;
+
+    Vec4f cbufferdata[512 + bindOffset];
+
+    for(int i = 0; i < bindOffset; i++)
+      cbufferdata[i] = Vec4f(-99.9f, -88.8f, -77.7f, -66.6f);
 
     for(int i = 0; i < 512; i++)
-      cbufferdata[i] = Vec4f(float(i * 4 + 0), float(i * 4 + 1), float(i * 4 + 2), float(i * 4 + 3));
+      cbufferdata[i + bindOffset] =
+          Vec4f(float(i * 4 + 0), float(i * 4 + 1), float(i * 4 + 2), float(i * 4 + 3));
 
     AllocatedBuffer cb(
         this, vkh::BufferCreateInfo(sizeof(cbufferdata), VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT |
@@ -638,8 +644,9 @@ float4 main() : SV_Target0
 
     vkh::updateDescriptorSets(
         device, {
-                    vkh::WriteDescriptorSet(descset, 0, VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
-                                            {vkh::DescriptorBufferInfo(cb.buffer)}),
+                    vkh::WriteDescriptorSet(
+                        descset, 0, VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
+                        {vkh::DescriptorBufferInfo(cb.buffer, bindOffset * sizeof(Vec4f))}),
                 });
 
     while(Running())