diff --git a/Source/Core/VideoBackends/Software/SWVertexLoader.cpp b/Source/Core/VideoBackends/Software/SWVertexLoader.cpp
index 2e6e748a38..751240bb2e 100644
--- a/Source/Core/VideoBackends/Software/SWVertexLoader.cpp
+++ b/Source/Core/VideoBackends/Software/SWVertexLoader.cpp
@@ -3,6 +3,7 @@
 
 #include "VideoBackends/Software/SWVertexLoader.h"
 
+#include <cfenv>
 #include <cstddef>
 #include <limits>
 
@@ -78,6 +79,10 @@ void SWVertexLoader::DrawCurrentBatch(u32 base_index, u32 num_indices, u32 base_
     SetFormat();
     ParseVertex(VertexLoaderManager::GetCurrentVertexFormat()->GetVertexDeclaration(), index);
 
+    // At least the position transform uses round-to-zero.
+    const auto round_mode = std::fegetround();
+    std::fesetround(FE_TOWARDZERO);
+
     // transform this vertex so that it can be used for rasterization (outVertex)
     OutputVertexData* outVertex = m_setup_unit.GetVertex();
     TransformUnit::TransformPosition(&m_vertex, outVertex);
@@ -85,6 +90,8 @@ void SWVertexLoader::DrawCurrentBatch(u32 base_index, u32 num_indices, u32 base_
     TransformUnit::TransformColor(&m_vertex, outVertex);
     TransformUnit::TransformTexCoord(&m_vertex, outVertex);
 
+    std::fesetround(round_mode);
+
     // assemble and rasterize the primitive
     m_setup_unit.SetupVertex();
 
diff --git a/Source/Core/VideoBackends/Software/TransformUnit.cpp b/Source/Core/VideoBackends/Software/TransformUnit.cpp
index 6fcf42df9e..83a81ee324 100644
--- a/Source/Core/VideoBackends/Software/TransformUnit.cpp
+++ b/Source/Core/VideoBackends/Software/TransformUnit.cpp
@@ -61,8 +61,7 @@ static void MultipleVec3Perspective(const Vec3& vec, const Projection::Raw& proj
 {
   result.x = proj[0] * vec.x + proj[1] * vec.z;
   result.y = proj[2] * vec.y + proj[3] * vec.z;
-  // result.z = (proj[4] * vec.z + proj[5]);
-  result.z = (proj[4] * vec.z + proj[5]) * (1.0f - (float)1e-7);
+  result.z = proj[4] * vec.z + proj[5];
   result.w = -vec.z;
 }