Computer challenges in ages past. Fritz 6 vs. Steve Ham

[Dan Andersson]

I decided to check how current engine hardware combinations fared on the instructive position after move 56:

[D]8/1k6/1pR5/1K6/P2b4/8/8/8 w - - 0 1

Fritz 6 on a PIII 500 MHz had no chance at correspondence level time controls. It might be interesting to see what it might find on modern hardware.

It seems like Stockfish and Spark on a i3 now does the job in tournament time control territory. It might conceivably find a forced mate inside a reasonable time-frame.

MvH Dan Andersson

[LaurenceChen]

It is a mate in 36 for White according to 6 men tablebases.

[AdminX]

Analysis by Deep Onno 1-2-70:

1.Rd6 Bf2 2.Rd7+ Kb8 3.Kc6 Be3 4.Rg7 Bd4 5.Rc7 Bc5 6.Rb7+ Ka8 7.Rh7 Be3 8.Rg7 Bd4 9.Rd7 Be3 10.Kd5 Bg1 11.Ke5 Bc5 12.Rh7 Kb8
+- (2.95) Depth: 20/30 00:00:02 4409kN, tb=13746
+- (2.94) Depth: 22/34 00:00:04 10791kN, tb=41591

1.Re6 Kb8 2.Re8+ Kc7 3.Re1 Bf2 4.Re7+ Kb8 5.Kc6 Ka8 6.Re8+ Ka7 7.Rg8 Be3 8.Kb5 Bd4 9.Re8 Kb7 10.Re7+ Kc8 11.Re2 Bg1 12.Re8+ Kc7 13.Re7+ Kc8 14.Kc6 Kb8 15.Rb7+ Ka8 16.Rh7 Kb8 17.Rf7 Be3 18.Rf3 Bd4 19.Rf8+ Ka7 20.Kb5 Be3 21.Rf3 Bd4 22.Rf7+ Kb8 23.Kc4 Be3 24.Kd5 Bc1 25.Rh7 Bb2 26.Re7 Ba3 27.Rh7
+- (2.95) Depth: 22/34 00:00:04 11956kN, tb=47089
+- (2.95) Depth: 44/57 00:04:55 907mN, tb=5364550

1.Rh6 Bf2 2.Rh7+ Kb8 3.Ka6 Bd4 4.Rh5 Be3 5.Rb5 Kc7 6.Ka7 Bc5 7.Ka8 Be3 8.Rb4 Bc5 9.Rb2 Kc6 10.Kb8 Bd6+ 11.Ka7 Bc5 12.Ka6 Kc7 13.Rc2 Kc6 14.Rc1 Kd6 15.Kb7 Bf2 16.Rd1+ Ke6 17.Kc6 Ke7 18.Rf1 Bd4 19.Rb1 Ke6 20.Rxb6
+- (3.74) Depth: 44/60 00:07:42 1659mN, tb=6922430
+- (#36) Depth: 49/68 00:15:32 3269mN, tb=13267480

[AdminX]

Notes from the game at the time showed:

[d][d]8/2k5/1pR5/1K6/P2b4/8/8/8 b

"Now dear reader, you are entitled to some much needed humor. As you see from my previous commentary, I've written that the position is drawn and many strong masters agreed with me. In fact, several OTB and Correspondence Masters heaped sympathy upon me for the following dilemma. How do I explain to weaker players that the position is a draw and that White can't make progress, in spite of the chess engine's evaluation of a win? I don't want to spend the rest of my life playing this endgame out with Fritz 6a while it exhausts every possible move until it agrees the position is a draw. So the other masters advised me to play just a few more moves until it is evident that the chess engine has no plan other than forcing


After 56. Rc6+

"my King or Bishop to move. Then we all agreed that everyone would be satisfied that Fritz was given every chance to prove itself, but failed.
So do you, dear reader, see that the position is drawn? Do you understand that if the pawns are exchanged that Black has a book draw by putting his King on a8? Do you see that Black's King and Bishop hold the b-pawn so White can make no headway? If you agree with me about this, then we are totallyWRONG! At least that's what Bobby Fischer says.

[D]8/1k6/1pR5/1K6/P2b4/8/8/8 w - - 0 1

57. Re6, …

"Now it is difficult for me to predict Fritz's moves because it totally lacks a plan. Apparently it wants to back my King up to the back rank. A related but equally futile plan is to kick my Bishop around a few times before trying to squeeze my King with 57 Rc4, Bf2 58 Rf4, Be3 59 Rf7+, Kc8 60 Kc6, Kb8 61 Rf8+, Ka7, which draws. Regardless, Fritz 6a calculated for 17 hours and 50 minutes to a depth of 26/40 ply, at an average speed of 368 kilonodes/second. It still favors its position by 2.69 pawns."

Source:
http://www.correspondencechess.com/camp ... _hambl.htm

[Linshark]

"Last Updated: 2001.01.31 "

Much has happened in the last 9 years

[kgburcham]

Dan you can see six threads at 100% without hyperthreading.
Also each core is 4100mhz so about 24 gig.
without tablebases

Deep Fritz 6

[kgburcham]

[D] 8/1k6/1pR5/1K6/P2b4/8/8/8 w - - 0 1

Deep Fritz 6:

1.Rd6
+- (2.72) Depth: 23/34 00:00:10 53787kN, tb=131118
1.Rd6 Be3 2.Re6 Bf2 3.Re7+ Kc8 4.Kc6 Kb8 5.Kd5 Bg1 6.Rd7 Be3
+- (2.69) Depth: 24/37 00:00:19 113mN, tb=223320
1.Rc4
+- (2.72) Depth: 24/37 00:00:19 114mN, tb=228105
1.Rc4 Be3 2.Rh4 Bf2 3.Rh7+ Kc8 4.Kc6 Kb8 5.Kd5 Kc8 6.Rf7 Be3
+- (2.66) Depth: 25/37 00:00:31 192mN, tb=324508
1.Rd6
+- (2.69) Depth: 25/37 00:00:31 193mN, tb=328607
1.Rd6 Be3 2.Re6 Bf2 3.Rh6 Kc7 4.Rh7+ Kc8 5.Kc6 Kb8 6.Kd5 Kc8
+- (2.66) Depth: 26/39 00:01:07 519mN, tb=594134
1.Rd6 Be3 2.Re6 Bf2 3.Rh6 Kc7 4.Rh7+ Kc8 5.Kc6 Kb8 6.Kd5 Kc8
+- (2.66) Depth: 27/41 00:01:41 750mN, tb=852784
1.Rc4
+- (2.69) Depth: 27/41 00:01:42 753mN, tb=864225
1.Rc4 Be3 2.Re4 Bf2 3.Re7+ Kc8 4.Kc6 Kb8 5.Kd5 Bg1 6.Rd7 Be3
+- (2.63) Depth: 28/39 00:03:35 1814mN, tb=1792843
1.Rc4 Be3 2.Re4 Bf2 3.Re7+ Kc8 4.Kc6 Kb8 5.Kd5 Bg1 6.Rd7 Be3
+- (2.66) Depth: 29/41 00:06:06 2918mN, tb=2769954

[yanquis1972]

would be more interesting without TBs, as obviously fritz 6 did not have them at the time.

[AdminX]

would be more interesting without TBs, as obviously fritz 6 did not have them at the time.

Are you sure about that??

[Dan Andersson]

Fritz 6 is actually not close to finding the win in the lines shown Score is way to low for that.

MvH Dan Andersson