Originally posted by dirtysniper
So the just of it is the engines cannot be beat? My apologies if my post came across as trying to brag or be untruthful , that was not my intention. I am unsure of the ELO on Shredder 11 , but I made no changes before starting the game. The draw with Fritz 9 shows the date, and the ELO as 2930. I did not take back any moves or use hints. I am not posting I would beat anyone 1400 and up , thus the reason for continuing to play against these engines.
SwissGambit correctly points out that these strong engines can be beaten, but usually only by very strong players. It's almost impossible to determine what went on in those two games you didn't lose without analyzing the two games to determine whether you miraculously played like a GM (possible, but highly unlikely) or the engine somehow played badly (more likely).
When it comes to computers, sometimes strange things happen. It's conceivable that during those two games, your PC's CPU was being used for some other high-priority task and the CPU was only allocating a tiny portion of its power to the chess game.
Chess engines also have been known to blunder, but these blunders are extremely rare. In 2005, Shredder 9.0 played in the Copa Mercosur tournament in Argentina. Against Pablo Lafuente in the third round, Shredder inexplicably blundered away a piece and lost the game. No clear reason could be determined for the blunder. Hardware failure was eliminated as a possible cause, and it was speculated that a "one-in-a-million" hash table collision may have been the cause of the bizarre blunder.
http://www.chessbase.com/newsdetail.asp?newsid=2538
http://chessmind.powerblogs.com/posts/1121752102.shtml
http://www.chessninja.com/dailydirt/2005/07/computer-blunder.htm
http://www.xs4all.nl/~timkr/chess2/diary_15.htm