C# rolled vs unrolled loop

gistfile1.cs

using System;
using System.Diagnostics;
using System.Windows.Forms;

namespace Test
{
    static class Program
    {
        [STAThread]
        static void Main(string[] args)
        {
            RolledLoop();
            UnrolledLoop();
        }

        public unsafe static void RolledLoop()
        {
            const int len = 256 * 256;
            int* data = stackalloc int[len];
            int* ptr = data;

            int count = len;

            var sw = Stopwatch.StartNew();

            while (count-- > 0)
            {
                *(ptr++) = 0;
            }

            Debug.WriteLine(string.Format("65536 rolled loop:   {0}ms", (sw.ElapsedTicks / (double)Stopwatch.Frequency)));
        }

        public unsafe static void UnrolledLoop()
        {
            const int len = 256 * 256;
            int* data = stackalloc int[len];
            int* ptr = data;

            int count = len;
            int rem = count % 8;
            count /= 8;

            var sw = Stopwatch.StartNew();

            while (count-- > 0)
            {
                *(ptr++) = 0;
                *(ptr++) = 0;
                *(ptr++) = 0;
                *(ptr++) = 0;

                *(ptr++) = 0;
                *(ptr++) = 0;
                *(ptr++) = 0;
                *(ptr++) = 0;
            }

            while (rem-- > 0)
            {
                *(ptr++) = 0;
            }

            Debug.WriteLine(string.Format("65536 unrolled loop: {0}ms", (sw.ElapsedTicks / (double)Stopwatch.Frequency)));
        }
    }
}