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Up Topic Rybka Support & Discussion / Rybka Discussion / Did Rybka Miss a win in the endgame
- - By dragon49 (****) Date 2009-08-05 01:27
Could somebody with strong hardware please look at this.  Rybka had a strong eval until the very end.  I suspect she missed a win somewhere.

Thanks
Attachment: 0809.pgn (10k)
Parent - By yanquis1972 (****) Date 2009-08-05 02:24
maybe so, but it just looks like a very tough endgame to me, i dont think draw is a bad result. it would take too much time for me at least to try to find a win. 

probably the real problem was rybka's eval was far too optimistic which tends to happen in endgames for some reason.  i really hope it gets fixed for v4 because as someone who is v bad in endgames, engines are often my best source & rybka can be WAY off in its eval of endgames at times, this is one of the very few problems i have w/ it.
Parent - By Felix Kling (Gold) Date 2009-08-05 11:19
Rybka tends to misevaluate endgames being an exchange up and rook endgames. This is actually both, so... :)
Parent - - By sylvain.renard.27 (**) Date 2009-08-11 20:31
Hello,
it looks like a winning endgame.
  Best regards,
   Sylvain

8/8/1r6/3k4/7R/1rBK1P1P/6P1/8 w - - 0 88


[+5.12]  d=37  1.Rh5 (127:01.08) 120309247kN
[+4.40]  d=37  1.Rh5 (66:01.10) 53380856kN
[+4.00]  d=37  1.Rh5 (61:07.02) 50921071kN
[+3.80]  d=37  1.Rh5 (58:51.38) 49970754kN
[+3.60]  d=36  1.Rh5 Ke6 2.Rh6 Kf7 3.Rxb6 Rxb6 4.h4 Rh6 5.g3 Rh5 6.Bd4 Rh6 7.Bf2 Rd6 8.Ke2 Rf6 9.g4 Rf4 10.Be3 Rc4 11.h5 Ra4 12.Kd3 (55:45.59) 48119215kN
[+3.60]  d=35  1.Rh5 Ke6 2.Rh6 Kf7 3.Rxb6 Rxb6 4.h4 Rh6 5.g3 Rh5 6.Bd4 Rh6 7.Bf2 Rd6 8.Ke2 Rf6 9.g4 Rf4 10.Be3 Rc4 11.h5 Ra4 12.Kd3 (54:38.42) 47219972kN
[+3.60]  d=34  1.Rh5 Ke6 2.Rh6 Kf7 3.Rxb6 Rxb6 4.h4 Rh6 5.g3 Rh5 6.Bd4 Rh6 7.Bf2 Rd6 8.Ke2 Rf6 9.g4 (54:04.54) 46758232kN
[+3.60]  d=33  1.Rh5 Ke6 2.Rh6 Kf7 3.Rxb6 Rxb6 4.h4 Rh6 5.g3 Rh5 6.Bd4 Rh6 7.Bf2 Rd6 8.Ke2 Rf6 9.g4 (53:46.44) 46517268kN
[+3.60]  d=33  1.Rh5 (53:45.02) 46486545kN
[+2.80]  d=33  1.Rh5 (53:12.53) 46252496kN
[+2.40]  d=33  1.Rh5 (52:51.25) 46059249kN
[+2.20]  d=33  1.Rh5 (52:36.04) 45898258kN
[+2.00]  d=32  1.Rh5 Ke6 2.h4 Kd7 3.Rc5 Rd6 4.Ke4 Rd1 5.h5 Rc1 6.Kd3 Rd1 7.Ke2 Rc1 8.Kd2 Rf1 9.Rg5 Rh1 10.g4 Rh2 11.Kd3 Rh3 12.Rd5 (23:40.37) 21026816kN
[+1.99]  d=31  1.Rh5 Ke6 2.h4 Kd7 3.Rc5 Rd6 4.Ke4 Rd1 5.h5 Rc1 6.Kd3 Rd1 7.Ke2 Rc1 8.Kd2 Rf1 9.Rg5 Rh1 10.g4 Rh2 11.Kd3 Rh3 12.Rd5 Ke6 13.Re5 (12:32.47) 11119867kN
[+1.82]  d=30  1.Rh5 Ke6 2.h4 Kd7 3.Rc5 Rd6 4.Ke4 Rd1 5.h5 Rc1 6.Kd3 Kd6 7.Rc8 Kd7 8.Rc4 Rf1 9.Ke4 Rc1 10.Rd4 (5:35.22) 4986832kN
[+1.81]  d=29  1.Rh5 Ke6 2.h4 Kd7 3.Rd5 Ke6 4.Rc5 Rd6 (3:21.52) 2988495kN
[+1.77]  d=28  1.Rh5 Ke6 2.h4 Kd7 3.Rd5 Ke6 4.Rc5 (2:10.12) 1888954kN
[+1.75]  d=27  1.Rh5 Ke6 2.h4 Rb7 3.Kc4 Rb1 4.Rh6 Ke7 5.g4 Rc7 6.Kd3 Rc5 7.Bf6 Kd7 8.h5 Ra5 9.Rh7 Ke6 10.Bc3 Rc5 11.Rh6 Kd7 12.Bd4 Ra5 (1:13.47) 1041646kN
[+1.75]  d=26  1.Rh5 Ke6 2.h4 Rb7 3.Kc4 Rb1 4.Rh6 Ke7 5.g4 Rc7 6.Kd3 Rc5 7.Bf6 Kd7 8.h5 Ra5 9.Rh7 Ke6 10.Bc3 Ra3 11.Rc7 Rh1 12.Rc6 (1:03.32) 898976kN
[+1.26]  d=19  1.Rh5 Ke6 2.h4 Rb7 3.Kc4 Rb1 4.Rh6 Kd7 5.g4 Rc7 6.Kd3 Rc5 7.Bd4 Rd1 8.Ke3 Ra5 9.Rh7 Ke6 10.Rc7 Ra3 11.Bc3 Rc1 (0:00.31) 7998kN
Parent - - By dragon49 (****) Date 2009-08-11 21:50
Thanks for spending the time on this.

I'm looking at the lines now.

What hardware and os are you using?
Parent - By sylvain.renard.27 (**) Date 2009-08-12 07:30
My hardware: Q6600  3600 MHz, 8 Gb of RAM.
Rybka 3 64 bit with all 6 pieces tablebases, 2 Gb of hash tables.
(you need 8 Gb or RAM if you want to use 4 cores with all the tablebases)
Up Topic Rybka Support & Discussion / Rybka Discussion / Did Rybka Miss a win in the endgame

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