Difficult testposition.

[Stan Arts]

[d] 1k1r2r1/1pp1qpb1/p4n1p/3PNbp1/2QP4/2N1B3/PP3PPP/3R1K1R w - - 0 1

In a game today against Yace my engine played Qxa6 and went on to lose.
However Nc6+ !? would be hard to resist for almost any human. After some analysis it seems to work.
Any engine able to find Nc6+ in reasonable time?

Stan

[mclane]

m0 d 2, 12 s, -10.60, c4c7 e7c7 f1g1 f6d5 c3d5 d8d5 d1c1
m0 d 2, 12 s, +0.76, c4b3 b8a8 d1e1
m0 d 3, 12 s, +0.76, c4b3 b8a8 d1e1
m0 d 4, 12 s, +0.44, c4b3 b8a8 d1e1 g8e8 f2f3
m0 d 5, 12 s, +0.44, c4b3 b8a8 d1e1 g8e8 f2f3
m0 d 6, 12 s, +0.49, c4b3 b8a8 d1e1 g8e8 f1g1 e7f8 e3d2
m0 d 7, 13 s, +0.69, c4b3 b8a8 d5d6 d8d6 b3f7 e7f7 e5f7
m0 d 7, 16 s, +0.84, d1e1 f6e4 e3c1 e4d6 c4c5 b8a8 b2b3 g7e5 e1e5 f5d3 f1g1
m0 d 8, 42 s, +1.11, d1e1 d8d6 e3d2 b8a8 e5c6 e7d7 e1e5 b7c6 c4a6 a8b8 d5c6 d7c6 e5b5 c6b5
m0 d 9, 95 s, +0.13, d1e1 f6d7 c3a4 g7e5 d4e5 d7e5 c4d4 e5c6 d4c4
m0 d 9, 105 s, +0.58, c4b3 b8a8 b3c4 f5g4 f2f3 g4f5 d5d6 d8d6 c4f7 g8e8 f7e7 e8e7
m0 d 9, 169 s,>+1.48, e5c6 b7c6
m0 d 9, 171 s, +1.95, e5c6 b7c6 d5c6 f5c8 d4d5 f6g4 e3c5 d8d6 c5d6 e7d6 c4b3


1. e5-c6


AMD Duron 1500mhz
(12 seconds were hash-swapping:-)

[swami]

Hi Stan,

It seems this position is particularly not difficult for computers, many engines would find it in less time, I just chose 3 engines,Aristarch and Alfil found it.Abrok didn't find it in less time.

FEN: 2kr2r1/1pp1qpb1/p4n1p/3PNbp1/2QP4/2N1B3/PP3PPP/3R1K1R w - - 0 1

Alfil 7.6:

Code: Select all

 3/14	00:00	       4.383	0	+0.48	Kf1e2 Nf6d7 g2g4
  5/16	00:00	      21.928	281.128	+0.36	Kf1e1 Nf6g4 Ne5xg4 Bf5xg4 Nc3e2
  6/16	00:00	      64.857	297.509	+0.36	Kf1e2 Nf6e4 Nc3xe4 Bf5xe4 f2f3 Be4xd5
  6/16	00:00	     116.382	310.352	+0.36	Kf1e2 Nf6e4 Nc3xe4 Bf5xe4 f2f3 Be4xd5
  7/20	00:00	     167.457	325.159	+0.30	Kf1e1 Nf6g4 d5d6 Rd8xd6 Nc3d5 Qe7d8 Ne5xf7
  7/20	00:00	     243.115	324.153	+0.43	Rd1e1 Nf6g4 Ne5xg4 Bf5xg4 Be3f4 Qe7d6 Bf4e5
  7/20	00:00	     251.160	315.131	+0.43	Rd1e1 Nf6g4 Ne5xg4 Bf5xg4 Be3f4 Qe7d6 Bf4e5
  8/22	00:01	     505.906	344.622	+0.40	Rd1e1 Rd8e8 h2h3 Nf6d7 Ne5xd7 Qe7xd7 Rh1h2 Kc8b8
  9/22	00:02	     812.422	356.169	+0.37	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8d7 Qa6b5+
  9/24	00:03	   1.366.025	353.984	+0.37	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8d7 Qa6b5+
 11/27	00:05	   1.808.218	361.643	+1.06	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8d7 Qa6b5+ Kd7c8 d5d6
 14/34	00:29	  10.795.767	365.958	+0.94	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8b8 d5d6 Rd8xd6 Qa6b5+ Rd6b6 Qb5xf5 Rb6xb2
 15/38	01:09	  27.377.664	396.507	+0.94	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8b8 d5d6 Rd8xd6 Qa6b5+ Rd6b6 Qb5xf5 Rb6xb2 Be3c1

Aristarch 4.50:

Code: Select all

   2	00:00	           2	2	-0.42	e5f7 ? e7f7
   2	00:00	          51	51	-3.42	e5f7 e7f7
   2	00:00	          97	97	-3.41	e3g5 !! h6g5
   2	00:00	         142	142	-3.21	e3g5 !! h6g5
   2	00:00	         187	187	-3.07	e3g5 h6g5
   2	00:00	         277	277	-3.06	h2h4 !! g5h4
   2	00:00	         324	324	-2.86	h2h4 !! g5h4
   2	00:00	         389	389	+0.17	h2h4 f6g4
   2	00:00	         445	445	+0.18	f2f4 !! g5f4
   2	00:00	         497	497	+0.22	f2f4 f6e4
   2	00:01	         549	549	+0.23	b2b4 !! f6e4
   2	00:01	         600	600	+0.28	b2b4 d8e8
   2	00:01	         659	659	+0.29	b2b3 !! d8e8
   2	00:01	         709	709	+0.29	b2b3 d8e8
   2	00:01	         757	757	+0.30	d5d6 !! e7d6
   2	00:01	         803	803	+0.32	d5d6 d8d6
   2	00:01	         888	888	+0.33	d1e1 !! d8e8
   2	00:01	         939	939	+0.53	d1e1 !! d8e8
   2	00:01	         990	990	+0.56	d1e1 d8e8
   3	00:01	       1.358	1.358	+0.74	d1e1 f6e4 f2f3
   4	00:01	       3.085	102.833	+0.58	d1e1 f6g4 d5d6 d8d6
   5	00:01	      15.144	189.300	+0.60	d1e1 g8e8 e3d2 d8d6 c4c5
   6	00:01	      45.019	180.076	+0.41	d1e1 g8e8 e3d2 d8d6 c4c5 c8b8
   7	00:01	     178.812	255.445	+0.53	d1e1 f6e4 g2g4 e4d6 c4e2 f5g6 e5g6
   8	00:02	     602.460	298.247	+0.44	d1e1 d8e8 f2f4 f6d7 b2b3 g5f4 e3f4 e7h4 f4g3
   9	00:04	   1.934.517	442.681	+0.51	d1e1 d8e8 f2f3 c8b8 e3d2 b8a8 g2g4 f5c2 f1g2
  10	00:13	   6.086.440	462.847	+0.22	d1e1 d8e8 b2b4 f6d7 e5d7 e7d7 b4b5 a6b5 c3b5 g7f6 e1c1 f6d8
  10	00:15	   6.938.051	473.587	+0.23	e5c6 !! b7c6 d5c6 d8e8 c4a6 c8b8 a6b5 b8a8 b5f5 e7b4
  10	00:15	   7.024.928	471.471	+0.43	e5c6 !! b7c6 d5c6 d8e8 c4a6 c8b8 a6b5 b8a8 b5f5 e7b4
  10	00:17	   7.957.470	463.992	+1.88	e5c6 e7d6 c6d8 g8d8 h2h4 g5g4 c4c5 f6d5 c3d5 d6d5 e3f4
  11	00:19	   8.675.165	465.156	+1.90	e5c6 e7d6 c6d8 g8d8 d1c1 f6d5 c3d5 d6d5 c4c7
  12	00:24	  11.212.611	472.109	+1.83	e5c6 e7d6 c6d8 g8d8 f1e1 f6d5 c3d5 d6d5 c4d5 d8d5
  13	00:34	  17.014.061	493.161	+1.83	e5c6 e7d6 c6d8 g8d8 d1c1

[Mike S.]

D945 3.4 GHz, 512 MB hash

Analysis by Rybka 2.3.2a 32-bit :

1.h4 Sg4 2.Sxg4 Lxg4 3.Te1 Tge8 4.hxg5 hxg5 5.f3 Lf5
= (-0.14) Tiefe: 9 00:00:00 3kN
= (-0.12) Tiefe: 10 00:00:02 120kN
1.f3 Td6 2.g4 Lg6 3.Kg2 Dd8 4.Sxg6 fxg6 5.The1
= (0.00) Tiefe: 10 00:00:05 259kN
= (-0.14) Tiefe: 11 00:00:11 615kN
1.h4 Sg4 2.Sxg4 Lxg4 3.Te1 Tge8 4.hxg5 hxg5 5.f3 Df6 6.Kg1 Lf5 7.Th5 Lg6
= (-0.05) Tiefe: 11 00:00:14 695kN
= (-0.14) Tiefe: 14 00:01:08 3375kN
1.Sc6+ bxc6 2.dxc6 Lc8 3.d5 Sg4 4.Lc5 Td6 5.Se4 Ka8 6.Te1 Se5 7.Db3 Te8
± (0.94) Tiefe: 14 00:01:46 5325kN
± (0.91) Tiefe: 15 00:01:59 5856kN

For analysis, I use slightly different engine settings, with Outlook: Slightly Optimistic because I think, the tendency is that in analysis it is more often about to find something active or aggressive for the side to move.

Analysis by Rybka 2.3.2a 32-bit SO-An:

1.Te1 Sd7 2.Sxd7+ Dxd7 3.h4 g4 4.Lf4 Tge8 5.Le5 De7
³ (-0.28) Tiefe: 5 00:00:00
1.Db3 Ka8 2.h3 Tde8 3.a4 Sd7 4.g4 Lh7 5.Sxd7 Dxd7 6.Kg2 Te7 7.The1 Tge8
= (-0.14) Tiefe: 5 00:00:00
= (-0.14) Tiefe: 10 00:00:05 260kN
1.f3 g4 2.Db3 Ka8 3.d6 Txd6 4.Dxf7 Dd8 5.f4 Le6 6.Dg6 Sd5 7.Sxd5 Lxd5 8.Df5 De8
= (-0.05) Tiefe: 10 00:00:07 373kN
= (-0.21) Tiefe: 11 00:00:10 531kN
1.Db3 Ka8 2.Te1 Tge8 3.h4 g4 4.Kg1 h5 5.Lg5 Dd6 6.Kh2 Kb8 7.Dc4 Td7 8.Dc5 Sxd5 9.Sxd5 Lxe5+ 10.Txe5 Txe5 11.Dxd6 Txd6 12.dxe5 Txd5
= (-0.10) Tiefe: 11 00:00:12 616kN
= (-0.05) Tiefe: 13 00:00:57 2873kN
1.Sc6+ bxc6 2.dxc6 Lc8 3.d5 Sg4 4.Lc5 Td6 5.Db4+ Ka8 6.Se4 Le5 7.Te1 Dd8 8.Sxd6 cxd6 9.Lb6 De7 10.f3 Sf6 11.Dc4 g4 12.fxg4 Sxg4
± (1.11) Tiefe: 13 00:01:23 4142kN
± (1.01) Tiefe: 15 00:01:45 5006kN

At first I thought, what's wrong with 1.Qxa6 (1...bxa6 2.Nc6+ and 3.NxQ)? but Black probably replied 1...Nxd5 instead. Or maybe even 1...Qxe5 whereafter 2.Qa7+ would be a funny continuation (to recapture at e5 with check).

[swami]

It took Alfil only 2 seconds to find Nc6! Can you believe that?

Engines rating dont matter after all, in test positions.

[swami]

Romi beats Alfil's record of 2 seconds!

RomiChessNG4:

Code: Select all

   1	00:00	         223	223	+0.30	d5d6
   2	00:00	         398	398	+0.30	d5d6 d8d6
   3	00:00	       1.274	1.274	+0.30	d5d6 d8d6 e5f7
   4	00:00	       3.408	3.408	+0.30	d5d6 d8d6 e5f7 d6e6
   5	00:00	      16.885	16.885	+0.32	d5d6 d8d6 e5f7 d6c6 c4b3
   6	00:00	      42.131	1.053.275	+0.35	d5d6 d8d6 c4f7 e7f7 e5f7 d6e6
   7	00:00	      89.684	1.281.200	+0.30	d5d6 d8d6 c4f7 e7f7 e5f7 d6b6 d1d2
   8	00:00	     256.558	801.743	+0.38	h2h4 g5h4 h1h4 c8b8 d5d6 d8d6 e3h6 g7h6
   9	00:00	     820.327	1.093.769	+0.33	d5d6 d8d6 c4f7 e7f7 e5f7 d6b6 d1d2 c8b8 f7e5 g8e8
  10	00:01	   1.905.171	1.245.209	+0.63	e5c6 b7c6
  11	00:02	   2.784.774	1.295.243	+0.66	e5c6 b7c6 d5c6 d8e8 c4a6 c8d8 a6a8 f5c8 f1g1 g5g4 d1e1 e7d6 h2h3 g4g3 f2g3 d6g3
  12	00:03	   4.390.466	1.334.488	+0.66	e5c6 b7c6 d5c6 d8e8 c4a6 c8d8 a6a8 f5c8 f1g1 g5g4 d1e1 e7d6 h2h3 g4g3 f2g3 d6g3
  13	00:08	  11.652.213	1.438.544	+0.67	e5c6 b7c6 d5c6 d8e8 c4a6 c8d8 a6a8 f5c8 d1e1 g5g4 h2h3 h6h5 f1g1 e7d6
  14	00:13	  19.636.402	1.441.732	+0.94	e5c6 b7c6 c4a6 c8d7 a6c6 d7c8 g2g4 f5g4 c6a8 c8d7 a8c6 d7c8 c6a8 c8d7 a8c6 d7c8
  15	00:31	  45.991.883	1.483.609	+0.90	e5c6b7c6 c4a6 c8d7 a6c6 d7c8 g2g4 f6g4 c6a8 c8d7 a8c6 d7c8 c6a8 c8d7 a8c6 d7c8

Chiron087:

Code: Select all

  1/1	00:00	         202	202	+0.11	Qc4b3
  1/1	00:00	         211	211	+0.24	Rd1e1
  1/2	00:00	         250	250	+0.24	Rd1e1
  2/6	00:00	         311	311	-0.32	Rd1e1 Kc8b8
  2/6	00:00	         574	574	-0.02	f2f4 Kc8b8
  2/6	00:00	         716	716	-0.02	f2f4 Kc8b8
  3/19	00:00	       1.918	1.918	-0.20	f2f4 Nf6g4 Rd1e1
  3/19	00:00	       4.047	4.047	-0.20	f2f4 Nf6g4 Rd1e1
  4/19	00:00	       5.655	5.655	-0.46	f2f4 Nf6g4 Rd1e1 Kc8b8
  4/19	00:00	       8.628	8.628	-0.40	Qc4b3 Nf6g4 d5d6 Rd8xd6
  4/19	00:00	      12.429	12.429	-0.09	Ne5c6 b7xc6 Qc4xa6+ Kc8b8
  4/19	00:00	      19.277	19.277	-0.09	Ne5c6 b7xc6 Qc4xa6+ Kc8b8
  5/14	00:00	      22.398	22.398	-0.21	Ne5c6 b7xc6 Qc4xa6+ Kc8b8 d5xc6
  5/14	00:00	      31.811	31.811	-0.13	d5d6 Rd8xd6 Ne5xf7 Rd6c6 Qc4b3
  5/18	00:01	      50.033	50.033	-0.13	d5d6 Rd8xd6 Ne5xf7 Rd6c6 Qc4b3
  6/16	00:01	      58.698	58.698	-0.48	d5d6 Rd8xd6 Qc4xf7 Qe7xf7 Ne5xf7 Rd6e6
  6/16	00:01	      71.140	71.140	 0.00	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8
  6/19	00:01	      99.155	99.155	+0.04	Qc4c5 Qe7xc5 d4xc5 Bf5c2 Ne5xf7 Bc2xd1
  6/19	00:01	     151.072	151.072	+0.04	Qc4c5 Qe7xc5 d4xc5 Bf5c2 Ne5xf7 Bc2xd1
  7/18	00:01	     172.970	172.970	-0.19	Qc4c5 Qe7xc5 d4xc5 Rg8e8 Ne5f3 Kc8b8 Kf1e2
  7/18	00:01	     193.479	171.981	 0.00	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a8+
  7/23	00:01	     392.666	232.759	+0.02	Rd1e1 Rd8e8 Be3d2 Nf6d7 Ne5c6 Qe7d6 Re1xe8+
  7/23	00:01	     454.790	246.766	+0.02	Rd1e1 Rd8e8 Be3d2 Nf6d7 Ne5c6 Qe7d6 Re1xe8+
  8/26	00:02	     681.825	292.880	+0.19	Rd1e1 Rd8e8 h2h4 Nf6d7 Ne5xd7 Bf5xd7 h4xg5 h6xg5
  8/26	00:02	     733.059	297.025	+0.27	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8d7
  8/26	00:02	     806.909	305.647	+0.27	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8d7
  9/22	00:03	   1.018.111	334.245	+0.88	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 Rd1e1 Nf6xd5 Nc3xd5
  9/22	00:03	   1.121.291	341.752	+0.88	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 Rd1e1 Nf6xd5 Nc3xd5
 10/26	00:03	   1.328.591	364.997	+0.88	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 Rd1e1 Nf6xd5 Nc3xd5 Qd6xd5
 10/26	00:04	   1.592.190	389.003	+0.88	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 Rd1e1 Nf6xd5 Nc3xd5 Qd6xd5
 11/28	00:05	   2.147.385	426.830	+0.75	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 h4h5 Nf6xd5 Nc3xd5 Qd6xd5 Qc4xd5
 11/28	00:06	   2.839.044	464.731	+0.75	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 h4h5 Nf6xd5 Nc3xd5 Qd6xd5 Qc4xd5
 12/32	00:08	   4.003.402	496.576	+0.86	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 h4h5 Kc8b8 Rh1h4 Nf6xd5 Nc3xd5 Qd6xd5
 12/34	00:10	   5.739.079	531.593	+0.86	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 h4h5 Kc8b8 Rh1h4 Nf6xd5 Nc3xd5 Qd6xd5
 13/38	00:15	   8.294.940	549.006	+0.98	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 Nf6xd5 Nc3xd5 Qd6xd5 Qc4xd5 Rd8xd5 Kf1e2 Bf5c2 Rd1c1
 13/38	00:25	  14.415.178	573.738	+0.98	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 Nf6xd5 Nc3xd5 Qd6xd5 Qc4xd5 Rd8xd5 Kf1e2 Bf5c2 Rd1c1
 14/41	00:34	  19.857.726	581.911	+0.84	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 h2h4 g5g4 Qc4c5 Nf6xd5 Qc5xd6 Rd8xd6 Nc3xd5 Rd6xd5 Kf1e2 Bf5e4

Bright-0.2a:

Code: Select all

  1/3	00:00	           3	3	+0.17	Ne5d3
  1/4	00:00	          14	14	+0.65	Be3d2
  1/4	00:00	          17	17	+0.86	Rd1e1
  2/7	00:00	         127	127	+0.62	Rd1e1 Kc8b8
  3/10	00:00	         878	878	+0.76	Rd1e1 g5g4 Kf1g1
  4/12	00:00	       4.023	4.023	+0.01	Rd1e1 Nf6g4 Ne5xg4 Bf5xg4
  4/16	00:00	       6.074	6.074	+0.20	Kf1g1 Nf6g4 d5d6 Rd8xd6 Ne5xf7
  5/16	00:00	      19.259	94	+0.31	Kf1g1 Nf6g4 Ne5xg4 Bf5xg4 Rd1e1
  5/16	00:00	      46.115	174	+0.62	Qc4c5 Qe7xc5 d4xc5 Bf5c2 Rd1d4
  6/17	00:00	      57.861	185	+0.57	Qc4c5 Qe7xc5 d4xc5 Nf6e4 Ne5xf7 Rd8d7 Nc3xe4 Bf5xe4
  7/20	00:00	     138.449	316	-0.11	Qc4c5 Qe7xc5 d4xc5 Rg8e8 Ne5f3 Nf6e4 Nc3xe4 Bf5xe4
  7/23	00:00	     263.444	401	+0.42	h2h3 Nf6e8 d5d6 Rd8xd6 Ne5xf7 Rd6e6 Nf7e5
  7/24	00:01	     439.615	476	+0.63	Rd1e1 g5g4 Be3d2 Qe7f8 Bd2f4 Kc8b8 Kf1g1
  8/24	00:01	     559.929	504	+0.65	Rd1e1 g5g4 Be3f4 Rg8e8 Bf4d2 Qe7f8 h2h3 g4xh3
  9/34	00:02	   1.620.854	636	+0.56	Rd1e1 Rg8e8 h2h4 Nf6g4 Ne5f3 Ng4xe3+ Re1xe3 Qe7f6 h4xg5 h6xg5
 10/34	00:05	   3.506.916	701	+0.34	Rd1e1 Rd8e8 h2h4 g5g4 Be3d2 Qe7f8 Bd2f4 Kc8b8 Kf1g1 Qf8d6
 11/34	00:11	   8.657.989	749	+0.38	Rd1e1 Rd8e8 h2h4 g5g4 Be3d2 g4g3 f2xg3 Nf6h5 Bd2f4 f7f6 Ne5f3
 12/36	00:35	  27.168.299	763	+0.32	Rd1e1 Rd8e8 h2h4 g5g4 Be3f4 Nf6h5 d5d6 Qe7xd6 Qc4xf7 Nh5xf4 Qf7xf5+ Nf4e6 Ne5xg4 Bg7xd4 Ng4xh6
 12/40	00:51	  36.712.725	720	+0.63	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8b8 d5d6 Qe7d7 d6xc7+ Kb8xc7 Nc3b5+ Kc7b8 d4d5 Rd8c8 Be3a7+ Kb8a8 Ba7c5+ Ka8b8
 13/41	01:02	  45.380.470	724	+1.20	Ne5c6 b7xc6 Qc4xa6+ Kc8d7 Qa6xc6+ Kd7c8 Qc6a6+ Kc8b8 d5d6 Rd8xd6 Qa6b5+ Rd6b6 Qb5xf5 Rb6xb2 Be3c1 Rb2b6 Rd1e1 Rb6e6
 14/52	01:35	  72.682.614	761	+1.14	Ne5c6 Qe7d6 Nc6xd8 Rg8xd8 Rd1c1 Nf6d7 Qc4e2 Nd7f6 Qe2f3 Bf5g6 h2h4 g5g4 Qf3f4 Bg6d3+ Kf1g1 Qd6b4

[Jouni]

Mike, put Rybka to Ultra Optimistic, if You want combinations fast:

Analysis by Rybka 2.3.2a 32-bit UO (2,4 Ghz) :

1.Qb3 Ka8 2.Re1 Rd6 3.f3 Rb6
= (-0.11) Depth: 7 00:00:02 95kN
1.Qb3 Ka8 2.Re1 Rd6 3.f3 Rb6
= (-0.16) Depth: 8 00:00:03 120kN
1.h4 Ne4 2.hxg5 hxg5 3.Nxe4 Bxe4 4.d6 Rxd6
= (-0.14) Depth: 8 00:00:04 150kN
1.h4 Ne4 2.hxg5 hxg5 3.Nxe4 Bxe4 4.d6 Rxd6 5.Qxf7 Qd8
= (-0.20) Depth: 9 00:00:05 214kN
1.Re1 Nd7 2.g4 Bxe5 3.dxe5 Nxe5 4.gxf5 Nxc4 5.Ba7+ Kxa7 6.Rxe7
= (0.04) Depth: 9 00:00:07 289kN
1.Re1 Nd7 2.g4 Bxe5 3.dxe5 Nxe5 4.gxf5 Nxc4 5.Ba7+ Kxa7 6.Rxe7 Nxb2 7.Kg2
= (-0.14) Depth: 10 00:00:09 366kN
1.f3 g4 2.Bf4 gxf3 3.Nxf3 Rde8 4.Re1 Qd8 5.Re5
= (0.00) Depth: 10 00:00:14 542kN
1.f3 g4 2.Bf4 gxf3 3.Nxf3 Ne4 4.Re1 Rde8 5.Nxe4 Bxe4 6.Kf2
= (-0.14) Depth: 11 00:00:21 832kN
1.Qb3 Ka8 2.Re1 Rd6 3.f3 Rb6 4.Qa3 Qxa3 5.bxa3 Re8
= (-0.14) Depth: 11 00:00:26 1020kN
1.Qb3 Ka8 2.Re1 Rd6 3.f3 Rb6 4.Qa3 Qxa3 5.bxa3 Rd8
= (-0.09) Depth: 12 00:00:45 1829kN
1.Nc6+ bxc6 2.dxc6 Bc8 3.d5 Ng4 4.Bc5 Qf6 5.d6 Rxd6 6.Qb3+ Ka8 7.Rxd6
± (0.79) Depth: 12 00:01:16 3006kN
1.Nc6+ bxc6 2.dxc6 Bc8 3.d5 Ng4 4.Bc5 Rd6 5.Ne4 Be5 6.Re1 Qd8
± (1.07) Depth: 13 00:01:31 3461kN
1.Nc6+ bxc6 2.dxc6 Bc8 3.d5 Ng4 4.Bc5 Rd6 5.Ne4 Ka8 6.Re1 Ne5 7.Qb4 Rgd8
± (0.95) Depth: 14 00:01:47 3974kN

Jouni

[Mike S.]

I chose slightly optimistic (and other changes), because I wanted a setting for general analysis, not for positions only where I suspect a deep combination. In such pos, I would rather use Rybka WinFinder or Hiarcs.

I have tried the ultra optimistic setting in some tactical positions, to compare it with default and with WinFinder. My impression is that WinFinder is superior in that type of tactical positions. I could be wrong though for the general average, because I didn't test that in very many positions.

Once again, I have updated my Quicktest results file:
http://members.aon.at/computerschach/quick/quickxls.zip

(see also http://members.aon.at/computerschach/quick/quicke.htm )

Rybka fans will not be amused about the 2.3.2a (default) result but Rybka WinFinder 2.2 is the new number one in that purely tactical test suite's results!

Generally I think, that in that specific sector or segment of the strength profile, there was not much improvement in recent years. Which means - obviously - almost all of the progress must come from other, 'non-combinative' segments. In other words, mostly positional (and maybe a bit from endgame improvements, sometimes).

[rightrook]

Hi Stan.........is Nc6+ a difficult test move?

Nah....

Simple!

A child could find that one...; in fact, Josh (age 7) finds it in only 2 seconds..!

CM-9000 regards



Robert

[Uri Blass]

I guess that when the position is modified and the black king is in a different square it is easy for engines to solve it.

Uri