SHA1 SpeedTest.cs

using System;
using System.Diagnostics;
using System.Security.Cryptography;

namespace SHA1Test {

    class Program {
        static void Main(string[] args) {
            var sha = SHA1.Create();
            var sw = new Stopwatch();

            sw.Start();
            var b = new byte[4 * (1 << 20)];
            long iterations = 10 * (1L << 30) / b.Length;
            for(int i = 0; i < iterations; i++) {
                sha.TransformBlock(b, 0, b.Length, null, 0);
            }

            var hash = sha.TransformFinalBlock(new byte[0], 0, 0);
            Console.WriteLine(sw.ElapsedMilliseconds);
            Console.Read();
        }
    }
}