difference in depth Rybka 3 vs Rybka 4

[kgburcham]

Brillant #21

[d] 8/3P3k/n2K3p/2p1n3/1b4N1/2p1p1P1/8/3B4 w - -


Ryb 3 21.02 3:33 +0.31++ 1.Nf6+ (197.253.714) 944
Ryb 4 23.01 3:39 +25.68++ 1.Nf6+ (341.315.367) 1552


Rybka 3

13.01 0:01 +0.27 1.Kxe5 Ba5 2.Nxe3 Kg6 3.Nd5 Kg5 4.Kd6 Nb8 5.Ne3 h5 6.Bc2 Nxd7 7.Kxd7 h4 8.gxh4+ (958.745) 814
14.01 0:02 +0.26 1.Kxe5 Ba5 2.Nxe3 Kg6 3.Nd5 Kg5 4.Kd6 Nb8 5.Nf4 Kf5 6.Ne6 Nxd7 7.Kxd7 Bb4 8.Kd6 Ke4 (1.978.695) 858
15.01 0:05 +0.21 1.Kxe5 Ba5 2.Nxe3 Kg6 3.Nd5 Kg5 4.Kd6 Nb8 5.Ne3 h5 6.Bc2 h4 7.gxh4+ Kxh4 8.Nc4 Bd8 9.Ne5 (4.383.803) 897
16.01 0:11 +0.16 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Nc4 Bd8 5.Na3 c4 6.Kc5 Nd3+ 7.Kd4 Bf6+ 8.Kd5 Kg6 9.Ke6 (10.055.525) 935
17.01 0:20 +0.11 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Nc4 Bd8 5.Na3 c4 6.Ba4 Kg6 7.Ke6 Kg7 8.Nc2 Nxc2 9.Bxc2 Kf8 (18.507.079) 936
18.01 0:32 +0.11 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Nc4 Bd8 5.Na3 c4 6.Ba4 Kg6 7.Ke6 Kg7 8.Nc2 Nxc2 9.Bxc2 Kf8 (29.917.368) 947
19.01 0:51 +0.11 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Nc4 Bd8 5.Na3 c4 6.Ba4 Kg6 7.Ke6 Kg7 8.Nc2 Nxc2 9.Bxc2 Kf8 (48.511.344) 958
20.01 1:24 +0.11 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Nc4 Bd8 5.Na3 c4 6.Ba4 Kg6 7.Ke6 Kg7 8.Nc2 Nxc2 9.Bxc2 Kf8 (79.518.508) 968
21.01 2:21 +0.11 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Nc4 Bd8 5.Na3 c4 6.Ba4 Kg6 7.Ke6 Kg7 8.Nc2 Nxc2 9.Bxc2 Kf8 (134.954.099) 976
21.02 3:33 +0.31++ 1.Nf6+ (197.253.714) 944
21.01 3:54 +0.51++ 1.Nf6+ (214.110.907) 935
21.01 4:23 +0.91++ 1.Nf6+ (238.934.808) 929
21.01 5:00 +1.71++ 1.Nf6+ (270.262.467) 921
21.01 5:30 +3.31++ 1.Nf6+ (296.508.094) 919
21.01 6:23 +6.51++ 1.Nf6+ (360.514.616) 961
21.01 8:05 +12.91++ 1.Nf6+ (538.958.934) 1137
21.01 8:53 +25.71++ 1.Nf6+ (624.298.723) 1198
21.01 9:15 +51.31++ 1.Nf6+ (664.347.888) 1225
21.01 9:34 +102.51++ 1.Nf6+ (699.873.348) 1247
21.01 9:45 +204.91++ 1.Nf6+ (718.997.184) 1257
best move: Ng4-f6 time: 13:00.141 min n/s: 1.434.921 nodes: 1.092.593.254


Rybka 4

16.00 0:01 +0.30 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kf6 Kg8 4.Ke7 Kg7 5.Bc2 Nxc2 6.Nxc2 Kg6 7.Ne3 Kg5 8.Kd6 Bd8 9.Kxc5 Kf6 10.Nd5+ Ke6 11.Nxc3 Kxd7 12.Kd5 Bc7 13.g4 Ke7 14.Kd4 (1.079.800) 1078
17.01 0:01 +0.21 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Bc2+ Nxc2 5.Nxc2 Kg6 6.Ne3 Bd8 7.Kxc5 Kf6 8.Nd5+ Ke6 9.Nxc3 Kxd7 10.Kd5 Bc7 11.g4 Ke7 12.Ne4 Kf7 13.Nc5 Kf6 14.Ne6 (1.772.498) 1069
18.01 0:02 +0.21 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Bf3 Kg7 5.Be4 Kf6 6.Bf5 Kg5 7.Bh7 h5 8.Bb1 Kf6 9.Be4 Kg5 10.Bb1 Kf6 11.Be4 Kg5 12.Bb1 Kf6 13.Be4 Kg5 14.Bb1 (2.753.186) 1107
19.01 0:03 +0.21 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Bf3 Kg7 5.Be4 Kf6 6.Bf5 Kg5 7.Bh7 Kf6 8.Bb1 Kg5 9.Be4 Kf6 10.Bf5 Kg5 11.Bh7 Kf6 12.Bb1 Kg5 13.Be4 Kf6 14.Bf5 (3.952.103) 1143
20.01 0:04 +0.21 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Bf3 Kg7 5.Be4 Kf6 6.Bf5 Kg5 7.Bh7 Kf6 8.Bb1 Kg5 9.Bf5 Kf6 10.Bb1 Kg5 11.Bf5 Kf6 12.Bb1 Kg5 13.Bf5 Kf6 14.Bb1 (5.932.871) 1193
21.01 0:07 +0.21 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Bf3 Kg7 5.Be4 Kf6 6.Bf5 Kg5 7.Bh7 Kf6 8.Bb1 Kg5 9.Bf5 Kf6 10.Bb1 Kg5 11.Bf5 Kf6 12.Bb1 Kg5 13.Bf5 Kf6 14.Bb1 (9.053.176) 1219
22.01 0:11 +0.21 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Bf3 Kg7 5.Be4 Kf6 6.Bf5 Kg5 7.Bh7 Kf6 8.Bb1 Kg5 9.Bf5 Kf6 10.Bb1 Kg5 11.Bf5 Kf6 12.Bb1 Kg5 13.Bf5 Kf6 14.Bb1 (14.448.217) 1229
23.01 0:27 +0.07 1.Kxe5 Ba5 2.Nxe3 Nb4 3.Kd6 Bb6 4.Ke7 Kg6 5.Ke6 Kg5 6.Kd6 Kf6 7.Bb3 Kg6 8.Be6 Kg5 9.Bf5 Kf6 10.Bb1 h5 11.Be4 Bd8 12.Kxc5 Na6+ 13.Kb5 Nb8 14.Bf5 (33.768.315) 1249
23.03 0:38 +0.33++ 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 Nxd8+ 6.Kf5 e2 7.Be4 e1Q 8.Bf3+ (47.593.201) 1224
23.01 0:40 +0.48++ 1.Nf6+ Kg7 2.Nh5+ (49.580.382) 1214
23.01 0:44 +0.88++ 1.Nf6+ Kg7 2.Nh5+ (53.681.918) 1200
23.01 0:51 +1.68++ 1.Nf6+ Kg7 2.Nh5+ (60.807.744) 1182
23.01 1:03 +3.28++ 1.Nf6+ Kg7 2.Nh5+ (75.252.211) 1177
23.01 1:36 +6.48++ 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 (115.442.900) 1198
23.01 2:44 +12.88++ 1.Nf6+ Kg7 2.Nh5+ (235.059.134) 1428
23.01 3:39 +25.68++ 1.Nf6+ Kg7 2.Nh5+ (341.315.367) 1552
23.01 4:16 +51.28++ 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nc4+ 5.Kd5 Kg4 6.Qh4+ Kf3 7.Kxc4 e2 8.Qf4+ Kg2 9.Be4+ Kg1 10.Qe3+ Kf1 11.Qf3+ Ke1 12.Bd3 Kd2 13.Qxe2+ Kc1 14.Qc2+ (405.423.647) 1580
23.01 8:13 +51.28++ 1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nc4+ 5.Kd5 Kg4 6.Qh4+ Kf3 7.Kxc4 e2 8.Qf4+ Kg2 9.Be4+ Kg1 10.Qe3+ Kf1 11.Qf3+ Ke1 12.Bd3 Kd2 13.Qxe2+ Kc1 14.Qc2+ (918.401.843) 1861
best move: Ng4-f6 time: 8:13.718 min n/s: 1.861.758 nodes: 918.401.843

[Graham Banks]

From the games I've observed, Rybka 4 has a different playing style too.

Cheers,
Graham.