diff --git a/GPU/Common/DrawEngineCommon.h b/GPU/Common/DrawEngineCommon.h
index 94ce1f35e7..23f42f8c1a 100644
--- a/GPU/Common/DrawEngineCommon.h
+++ b/GPU/Common/DrawEngineCommon.h
@@ -32,8 +32,8 @@ class VertexDecoder;
 
 enum {
 	VERTEX_BUFFER_MAX = 65536,
-	DECODED_VERTEX_BUFFER_SIZE = VERTEX_BUFFER_MAX * 64,
-	DECODED_INDEX_BUFFER_SIZE = VERTEX_BUFFER_MAX * 16,
+	DECODED_VERTEX_BUFFER_SIZE = VERTEX_BUFFER_MAX * 2 * 36,  // 36 == sizeof(SimpleVertex)
+	DECODED_INDEX_BUFFER_SIZE = VERTEX_BUFFER_MAX * 6 * 6 * 2,   // * 6 for spline tessellation, then * 6 again for converting into points/lines, and * 2 for 2 bytes per index
 };
 
 enum {
diff --git a/GPU/Common/SplineCommon.cpp b/GPU/Common/SplineCommon.cpp
index 5e514b31d7..ce6fef470b 100644
--- a/GPU/Common/SplineCommon.cpp
+++ b/GPU/Common/SplineCommon.cpp
@@ -548,7 +548,9 @@ void DrawEngineCommon::SubmitCurve(const void *control_points, const void *indic
 	output.indices = decIndex;
 	output.count = 0;
 
-	surface.Init(DECODED_VERTEX_BUFFER_SIZE / 2 / vertexSize);
+	int maxVerts = DECODED_VERTEX_BUFFER_SIZE / 2 / vertexSize;
+
+	surface.Init(maxVerts);
 
 	if (CanUseHardwareTessellation(surface.primType)) {
 		HardwareTessellation(output, surface, origVertType, points, tessDataTransfer);
diff --git a/GPU/Common/SplineCommon.h b/GPU/Common/SplineCommon.h
index f1a834b265..e3acec7a67 100644
--- a/GPU/Common/SplineCommon.h
+++ b/GPU/Common/SplineCommon.h
@@ -27,6 +27,7 @@
 #define HALF_CEIL(x) (x + 1) / 2 // Integer ceil = (int)ceil((float)x / 2.0f)
 
 // PSP compatible format so we can use the end of the pipeline in beziers etc
+// 8 + 4 + 12 + 12 = 36 bytes
 struct SimpleVertex {
 	float uv[2];
 	union {