C# - Calculates the GFLOPS Of A PC

CalculateThisPCGFLOPS.cs

public static double CalculateThisPCGFLOPS()
        {
            const int Flops  = 10_000_000;
            const int Loops  = 10;
            var       etl    = new List<double>();
            var       random = new Random();
            var       begE1  = Enumerable.Range(0, Flops).AsParallel().WithDegreeOfParallelism(Environment.ProcessorCount).Select(i => random.NextDouble()).ToArray();
            var       mulE1  = Enumerable.Range(0, Flops).AsParallel().WithDegreeOfParallelism(Environment.ProcessorCount).Select(i => random.NextDouble()).ToArray();
            for(var loop = 0; loop < Loops; ++loop)
            {
                var begE = begE1;
                var mulE = mulE1;
                var th1 = new Thread(() =>
                {
                    var timer = Stopwatch.StartNew();
                    for(var i = 0; i < Flops - 1; i++)
                        begE[i] += mulE[i] * 3.14;
                    timer.Stop();
                    begE  = begE1;
                    mulE  = mulE1;
                    timer = Stopwatch.StartNew();
                    for(var i = 0; i < Flops - 1; i++)
                        begE[i] += mulE[i] * 3.14;
                    timer.Stop();
                    etl.Add(timer.Elapsed.TotalMilliseconds);
                })
                {
                    Priority = ThreadPriority.Highest
                };
                th1.Start();
                th1.Join();
            }
            var at = Math.Round(Flops / etl.AverageEx() / 1000.0);
            return at;
        }