Test position: beautiful positional sacrifice

Discussion of anything and everything relating to chess playing software and machines.

Moderators: hgm, Dann Corbit, Harvey Williamson

Forum rules
This textbox is used to restore diagrams posted with the [d] tag before the upgrade.
User avatar
beachknight
Posts: 3533
Joined: Tue Jan 09, 2007 7:33 pm
Location: Antalya, Turkey
Contact:

Re: Test position: beautiful positional sacrifice

Post by beachknight » Wed Jan 22, 2014 2:11 pm

13: New game
r1bq1rk1/1pp2pbp/p2ppnp1/n2P4/2P5/P1N3P1/1P1NPPBP/R1BQ1RK1 b - - 0 1

Analysis by Stockfish PA_GTB DD 64:

10...exd5 11.cxd5 c6 12.dxc6 Nxc6 13.Nde4
= (0.15 ++) Depth: 39/57 03:27:19 25130MN
(Chess Engines Testing, 22.01.2014)
hi, merhaba, hallo HT

User avatar
beachknight
Posts: 3533
Joined: Tue Jan 09, 2007 7:33 pm
Location: Antalya, Turkey
Contact:

Re: Test position: beautiful positional sacrifice

Post by beachknight » Wed Jan 22, 2014 3:22 pm

13: New game
r1bq1rk1/1pp2pbp/p2ppnp1/n2P4/2P5/P1N3P1/1P1NPPBP/R1BQ1RK1 b - - 0 1

Analysis by Stockfish PA_GTB DD 64:

10...exd5 11.cxd5 b5 12.Qc2 Bf5 13.e4 Bd7 14.b4 Nc4 15.Nxc4 bxc4 16.Rb1 Rc8 17.b5 axb5 18.Nxb5 Bxb5 19.Rxb5 c3 20.a4 Qd7 21.Bg5 Ng4 22.h3 f6 23.Bf4
+/= (0.31 --) Depth: 39/57 04:13:46 30617MN
(Chess Engines Testing, 22.01.2014)
hi, merhaba, hallo HT

jdart
Posts: 4116
Joined: Fri Mar 10, 2006 4:23 am
Location: http://www.arasanchess.org

Re: Test position: beautiful positional sacrifice

Post by jdart » Wed Jan 22, 2014 3:29 pm

It might still be close to the next-best alternative. Quite a few exchange sacs are like that.

--Jon

Dan Astrachan
Posts: 134
Joined: Fri May 28, 2010 9:07 am

Re: Test position: beautiful positional sacrifice

Post by Dan Astrachan » Wed Jan 22, 2014 4:32 pm

Based on short analysis, less than 10...Rb8, it's White's 18.Na5 that decided the game: SF's eval drops by almost a full point after that move ;)
Computer used: Intel Core i7 875K @ 2.93GH, 4 cores, 12 Gb of RAM

User avatar
beachknight
Posts: 3533
Joined: Tue Jan 09, 2007 7:33 pm
Location: Antalya, Turkey
Contact:

Re: Test position: beautiful positional sacrifice

Post by beachknight » Wed Jan 22, 2014 6:10 pm

Next best move:

13: New game
r1bq1rk1/1pp2pbp/p2ppnp1/n2P4/2P5/P1N3P1/1P1NPPBP/R1BQ1RK1 b - - 0 1

Analysis by Stockfish PA_GTB DD 64:

10...Nd7 11.Qc2 Ne5 12.b3 exd5 13.cxd5 c5 14.Bb2 f5 15.Rab1 b5
= (0.21) Depth: 34/51 00:29:37 3664MN
(Chess Engines Testing, 22.01.2014)
hi, merhaba, hallo HT

User avatar
beachknight
Posts: 3533
Joined: Tue Jan 09, 2007 7:33 pm
Location: Antalya, Turkey
Contact:

Re: Test position: beautiful positional sacrifice

Post by beachknight » Wed Jan 22, 2014 6:51 pm

13: New game
r1bq1rk1/1pp2pbp/p2ppnp1/n2P4/2P5/P1N3P1/1P1NPPBP/R1BQ1RK1 b - - 0 1

Analysis by Stockfish PA_GTB DD 64:

10...Nd7 11.Qc2 Ne5 12.b3 exd5 13.cxd5 c5 14.Bb2 f5 15.e3 Bd7 16.Ne2 Rc8 17.Nf4 Qe7
+/= (0.33 --) Depth: 36/55 01:10:39 8763MN
(Chess Engines Testing, 22.01.2014)
hi, merhaba, hallo HT

User avatar
beachknight
Posts: 3533
Joined: Tue Jan 09, 2007 7:33 pm
Location: Antalya, Turkey
Contact:

Re: Test position: beautiful positional sacrifice

Post by beachknight » Wed Jan 22, 2014 7:15 pm

13: New game
r1bq1rk1/1pp2pbp/p2ppnp1/n2P4/2P5/P1N3P1/1P1NPPBP/R1BQ1RK1 b - - 0 1

Analysis by Stockfish PA_GTB DD 64:

10...Nd7 11.Qc2 exd5 12.cxd5 Ne5 13.Rb1 b5 14.h3 f5 15.b3 c5 16.dxc6 Be6 17.Nf3 Nxf3+ 18.Bxf3 Rc8 19.Na2
= (0.24) Depth: 36/55 01:33:04 11553MN
(Chess Engines Testing, 22.01.2014)
hi, merhaba, hallo HT

User avatar
beachknight
Posts: 3533
Joined: Tue Jan 09, 2007 7:33 pm
Location: Antalya, Turkey
Contact:

Re: Test position: beautiful positional sacrifice

Post by beachknight » Wed Jan 22, 2014 7:27 pm

13: New game
r1bq1rk1/1pp2pbp/p2ppnp1/n2P4/2P5/P1N3P1/1P1NPPBP/R1BQ1RK1 b - - 0 1

Analysis by Stockfish PA_GTB DD 64:

10...Nd7 11.Qc2 exd5 12.cxd5 Ne5 13.Rb1 b5 14.h3 f5 15.b3 c5 16.dxc6 Be6 17.Nf3 Nxf3+ 18.Bxf3 Rc8 19.Na2
= (0.24) Depth: 37/55 01:47:28 13334MN
(Chess Engines Testing, 22.01.2014)
hi, merhaba, hallo HT

User avatar
Eelco de Groot
Posts: 4279
Joined: Sun Mar 12, 2006 1:40 am
Location: Groningen

Re: Test position: beautiful positional sacrifice

Post by Eelco de Groot » Fri Jan 24, 2014 1:46 am

mar wrote:I accidentally let my engine run in the background (at work) and it found Rb8 at depth 42 after 19 hours (1 core, no multipv, 4 meg hash :). It switched to Rb8 after many iterations of exd5.
However the score it shows is -6 cp :)
The PV being: Rb8 b4 Nxc4 Nxc4 Nxd5 Nxd5 Bxa1 Nf4 Bg7 Qc2 Bd7 Rd1 Re8 Nd3 e5 Bb2 Qe7 e4 Be6 Ne3 c6 Re1 Qd8 Qc3 Rc8 f4 Qb6 a4 Rcd8 a5 Qa7 Bf3 Bd7 Qc2 Bh3 Kh1 Bh6 Bg2 Bxg2+ Kxg2 exf4 Nxf4 Bg7 Bxg7 Kxg7
An accidently left running Stockfish here, after many hours:

r1bq1rk1/1pp2pbp/p2ppnp1/n2P4/2P5/P1N3P1/1P1NPPBP/R1BQ1RK1 b - -

Engine: Sf20140119_001 MP (Q6700, 4 threads, 512 MB)
(Testversion, small change in pawns.cpp)
by Tord Romstad, Marco Costalba and Joona Kiiski

.
.
.
.
.
34/47 25:51 -0.23 10...exd5 11.cxd5 c6 12.Rb1 Nxd5
13.Nxd5 cxd5 14.Bxd5 Bf5 15.e4 Be6
16.b4 Nc6 17.Nc4 Rc8 18.Bb2 Bxd5
19.Qxd5 Ne7 20.Qd3 Bxb2 21.Nxb2 Nc6
22.f4 b5 23.Nd1 Qb6+ (3.575.186.268) 2304

35/49 42:42 -0.31-- 10...exd5 11.cxd5 c6 (5.888.267.626) 2297

35/51 95:25 -0.15++ 10...exd5 11.cxd5 Nd7 12.Rb1 b5 (13.349.425.723) 2331


35/54 151:58 -0.27 10...Rb8 11.b4 Nxc4 12.Nxc4 Nxd5
13.Nxd5 Bxa1 14.Bh6 Bg7 15.Bxg7 Kxg7
16.Nf4 Bd7 17.Qd2 Bb5 18.Ne3 e5
19.Nd3 f5 20.Rd1 Bxd3 21.Qxd3 f4
22.Nc4 Qf6 23.g4 Qg5 (21.380.954.765) 2344

36/54 157:46 -0.27 10...Rb8 11.b4 Nxc4 12.Nxc4 Nxd5
13.Nxd5 Bxa1 14.Bh6 Bg7 15.Bxg7 Kxg7
16.Nf4 Bd7 17.Qd2 Bb5 18.Ne3 e5
19.Nd3 f5 20.Rd1 Bxd3 21.Qxd3 f4
22.Nc4 Qf6 23.g4 Qg5 (22.214.894.014) 2346


37/54 182:14 -0.19++ 10...Nd7 11.Qc2 Ne5 12.b3 (25.840.216.716) 2363

37/54 201:32 -0.35-- 10...Nd7 11.Qc2 Ne5 12.b3 exd5
13.cxd5 (28.572.838.262) 2362

37/54 220:16 -0.23 10...Nd7 11.Qc2 Ne5 12.b3 exd5
13.cxd5 c5 14.Bb2 f5 15.h3 b5 16.e3 Re8
17.Ne2 Rb8 18.Bc3 Bd7 19.b4 Nb7
20.Nf3 Nxf3+ 21.Bxf3 Bxc3 22.Qxc3 Rc8
23.Rac1 Qe7 (31.284.223.126) 2367
.
.
.
.
.
40/58 557:29 -0.17 10...Nd7 11.Qc2 Ne5 12.b3 c6 13.Bb2 Rb8
14.dxc6 Naxc6 15.e3 b5 16.f4 Ng4
17.Nd1 Bxb2 18.Qxb2 Bb7 19.cxb5 axb5
20.Bf3 h5 21.Re1 Na5 22.h3 Nf6
23.Nf2 Bxf3 (80.599.344.653) 2409

41/58 597:29 -0.25-- 10...Nd7 11.Qc2 Ne5 12.b3 c6 (86.423.292.756) 2410

41/59 691:40 -0.33-- 10...Nd7 11.Qc2 Ne5 12.b3 exd5
13.cxd5 (100.380.647.629) 2418

41/65 908:43 -0.09++ 10...exd5 11.cxd5 c6 (131.961.934.489) 2420


41/65 1345:31-0.21 10...Rb8 11.b4 Nxc4 12.Nxc4 Nxd5
13.Nxd5 Bxa1 14.Bh6 Bg7 15.Bxg7 Kxg7
16.Nf4 Bd7 17.Qd2 Bb5 18.Nb2 Qf6
19.Rc1 Rfc8 20.a4 Bd7 21.Rc2 Qd8
22.e4 b6 23.Rc1 Qe7 (196.706.171.634) 2436

42/65 1416:43-0.13++ 10...Rb8 11.b4 Nxc4 (207.787.929.924) 2444

42/65 1472:09-0.05++ 10...Rb8 11.b4 Nxc4 (216.043.029.060) 2445

42/65 1527:35-0.29-- 10...Rb8 11.b4 Nxc4 12.Nxc4 Nxd5
13.Nxd5 (224.259.970.875) 2446

42/65 1553:38-0.28 10...Rb8 11.b4 Nxc4 12.Nxc4 Nxd5
13.Nxd5 Bxa1 14.Bh6 Bg7 15.Bxg7 Kxg7
16.Nf4 f6 17.e4 e5 18.Nd5 Be6 19.Qd2 c6
20.Nde3 Qc7 21.Qxd6 Qxd6 22.Nxd6 Rfd8
23.Ndc4 Rd4 (228.283.908.725) 2448

43/65 1572:04-0.20++ 10...Rb8 11.b4 Nxc4 12.Nxc4 Nxd5 (231.145.169.620) 2450

43/65 1645:18-0.13 10...Rb8 11.b4 Nxc4 12.Nxc4 Nxd5
13.Nxd5 Bxa1 14.Bh6 Bg7 15.Bxg7 Kxg7
16.Nf4 Bd7 17.Qd2 Bb5 18.Na5 c6
19.Rc1 d5 20.Nd3 Bxd3 21.exd3 e5
22.Nb3 Re8 23.a4 Qd7 (242.143.933.465) 2452

44/65 1737:51-0.21-- 10...Rb8 11.b4 Nxc4 12.Nxc4 (256.056.723.571) 2455

44/66 1872:07-0.21 10...Rb8 11.b4 Nxc4 12.Nxc4 (277.728.687.358) 2472


best move: Ra8-b8 time: 1871:47.896 min n/s: 2.472.495 nodes: 277.728.687.358
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan

leavenfish
Posts: 282
Joined: Mon Sep 02, 2013 6:23 am

Re: Test position: beautiful positional sacrifice

Post by leavenfish » Fri Jan 24, 2014 4:47 am

What's so 'beautiful' about it? Black just has a bad position and it's more a matter of the lesser evil than anything else.

Post Reply