OpenTK - VBO - Application crash

Question

I am learning OpenGL (using OpenTK). Today I want to use VBO to render my quads effectively. When I call render it crash

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Got a SIGSEGV while executing native code. This usually indicates a fatal error in the mono runtime or one of the native libraries used by your application.
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Full stacktrace can be found here

This is my render code:

GL.EnableVertexAttribArray(0);

GL.BindBuffer(BufferTarget.ArrayBuffer, _vbo);
GL.VertexAttribPointer(0, _count, VertexAttribPointerType.Float, false, 0, 0);

GL.DrawArrays(PrimitiveType.Quads, 0, _count);

GL.DisableVertexAttribArray(0);

And this is how I generate buffers.

GL.GenBuffers(1, out _vbo);
GL.BindBuffer( BufferTarget.ElementArrayBuffer, _vbo );

Vector3[] vertices;
_count = vertices.Length;

GL.BufferData<Vector3>(BufferTarget.ArrayBuffer, new IntPtr(vertices.Length * Vector3.SizeInBytes), vertices, BufferUsageHint.StaticDraw);

PS: I am not using any colors or textures for this.

Answer 1

Changed render code to this

        GL.BindBuffer( BufferTarget.ArrayBuffer, _vbo );
        GL.VertexPointer (3, VertexPointerType.Float, Marshal.SizeOf(new Vector3()), IntPtr.Zero);
        GL.EnableClientState (ArrayCap.VertexArray);

        GL.DrawArrays(PrimitiveType.Quads, 0, _count);

        GL.DisableClientState (ArrayCap.VertexArray);

and it worked. I used BufferTarget.ArrayBuffer everywhere (ElementArrayBuffer is for indices).