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What's the estimated cost for the whole machine (Superdome + hard drives)?

Out of my own curiosity, I did a few tests to test performance. I'm no performance test guru, but what I did was use an array of 271 palindromes and an array of 271 non-palidromes, then tested the array for x Iterations. The score on top is using the Array.Reverse method (the method I posted second) and the bottom score checking character by character (the method I posted first). The score is the average number of ticks per method call. The average non-palindrome was longer than the average palindrome, so that may account for the slightly slower performance.

Palindromes:

1000 Iterations
18.1072177121771
1000 Iterations
12.1946568265683

5000 Iterations
17.8115896678967
5000 Iterations
12.046842804428

10000 Iterations
17.2203335793358
10000 Iterations
11.4925402214022

15000 Iterations
17.121790897909
15000 Iterations
11.6280364083641

20000 Iterations
17.1833800738007
20000 Iterations
11.5294937269373

30000 Iterations
17.2080157441574
30000 Iterations
11.7019434194342

Non-Palindromes:

1000 Iterations
21.8025682656827
1000 Iterations
15.1509372693727

5000 Iterations
21.6547542435424
5000 Iterations
15.2248442804428

10000 Iterations
21.8764752767528
10000 Iterations
14.6335881918819

15000 Iterations
21.777932595326
15000 Iterations
14.6089525215252

20000 Iterations
22.0981963099631
20000 Iterations
14.6890184501845

30000 Iterations
22.3075995079951
30000 Iterations
14.7444487084871

The character by character method beating the Array.Reverse method on non-palindromes is a no brainer, because it returns false after the first check, where as the Array.Reverse has to reverse and test the whole string every time.

I was a bit surprised by it winning on palindromes, though. If anyone has any insight into this, I'd love to hear it. All I can assume is that a character by character check is more efficient than putting a string into an array, reversing it, and putting it back into a string.

public bool IsPalindrome(string palindrome)
{
   if(palindrome == null || palindrome.Length == 0)
      return false;
   palindrome = palindrome.Replace(" ", "").ToLower();
   char[] reverse = palindrome.ToCharArray();
   Array.Reverse(reverse);
   string s = new string(reverse);
   return palindrome == s;
}

Here's a case/space insensitive and smaller palindrome checker.

public bool IsPalindrome(string palindrome)
{
   if(palindrome == null || palindrome.Length == 0)
      return false;

   palindrome = palindrome.Replace(" ", "").ToLower();
   int start = 0, end = palindrome.Length - 1;

   while(end - start >= 1)
   {
      if(palindrome[start] == palindrome[end])
      {
         start++;
         end--;
      }
      else
         return false;
   }

   return true;
}

This will validate palindromes without case sensitivity even if they have spaces, for example: A man a plan a canal Panama