83 nice Testpositions (Long and big post).

[George Tsavdaris]

I suspect also that the following is wrong and it needs to be am Bxh6 bm 0-0

[D]2kr1nr1/pbp1qp2/1p2pn1p/8/3Pp2Q/P1P3N1/2PBBPPP/R3K2R w KQ - 0 1 am O-O; bm Bxh6;

I don't think so since after:
1.0-0 Ng6 2.Qxh6(2.Qh3 Nd5 -0.23 for Rybka 1.2i) Rh8 3.Qe3(3.Qg5 loses) Nd5 4.Qg5 Nxc3 and Rybka gives -0.32.

After 1.Bxh6 Ng6 2.Qg5 score is -0.08 for white after 18 plies of Rybka....
Since after for example 2...Rd5 3.Qc1! and Rybka after 18 plies gives a very small plus for white.

[George Tsavdaris]

Is George Tsavdaris somewhere around ?

Hi, i was not here lately, but i'm back.....
Here is a corrected, according to some of Uri's recommendations, EPD in which i have added also 5 new testpositions in the bottom:

---------------------
8/6p1/P1b1pp2/2p1p3/1k4P1/3PP3/1PK5/5B2 w - - 0 1 bm Bg2;
r1bqk2r/ppp1ppbp/2n3p1/3p4/2PP1B2/2P1P3/P4PPP/R2QKBNR w KQkq - 0 1 am cxd5; bm Nf3;
4r1k1/pp4p1/6p1/3q1pP1/2rPp2P/1QPnP3/PP4K1/1R2BR2 b - - 0 1 bm f4;
4k1rr/1R1R3p/8/8/8/2K5/7P/8 w k - 0 1 bm Rd2;
8/3R1P2/1ppP1p2/3r4/8/8/K4k2/8 b - - 0 1 bm f5;
r2q1r2/1b2bpkp/p3p1p1/2ppP1P1/7R/1PN1BQR1/1PP2P1P/4K3 w - - 0 1 bm Qf6+;
4k3/p7/B1bB1pp1/4n3/p2KP3/8/6P1/8 w - - 0 1 am Bxe5;
1R6/8/8/5bp1/4p2k/8/B1p2PKP/8 w - - 0 1 bm Rb1;
3k4/4pp2/n2n4/5BN1/3N4/b7/4K3/8 w - - 0 1 bm Nxf7+;
8/2B2pPb/7k/4K3/3p2P1/8/8/8 w - - 0 1 bm g8N+;
r5k1/7p/4p1pP/4P1P1/R3b3/8/7K/N7 w - - 0 1 am Rxe4; bm Rxa8;
r1b2rk1/pp2bppp/4p3/1PPp4/1n3B2/2N1P3/q3BPPP/2RQ1RK1 b - - 0 1 am Qa5; bm Qa3;
rn2k3/p4ppr/1p2p1n1/2ppP1Bp/q2P3P/P1P2QN1/2P2PP1/R4K1R w q - 0 1 bm Nf5;
rqb1k2r/1p3p1p/p1n2Pp1/3Qb3/4N3/4B3/PP2B1P1/R4R1K b kq - 0 1 am O-O; bm Bf5 Qc7;
8/p7/5k2/pPp1p3/2P3Kb/8/8/3B4 w - - 0 1 am Kxh4;
r3r3/p2n1pk1/2qpp2p/1p5n/3PN2p/1PPQ1P2/P1BB1P2/R6K w - - 0 1 bm Bxh6+;
6r1/2rp1kpp/2qQp3/p3Pp1P/1pP2P2/1P2KP2/P5R1/6R1 w - - 0 1 bm Rxg7+;
7b/8/kq6/8/8/1N2R3/K2P4/8 w - - 0 1 bm Nd4;
2r1r3/1b1n1pkp/1qnBp1p1/4P1N1/2R1B3/8/p2Q1PPP/3R2K1 w - - 0 1 bm Nxf7;
r5k1/p4n1p/6p1/2qPp3/2p1P1Q1/8/1rB3PP/R4R1K b - - 0 1 am Rxc2; bm Rf8;
8/pR4pk/1b6/2p5/N1p5/8/PP1r2PP/6K1 b - - 0 1 bm Rxb2;
nqr3k1/3b1p2/p2p2pp/1p1Pp1N1/1P2P3/1B5P/P2Q1PP1/5RK1 w - - 0 1 bm Ne6;
r1b1q1k1/1p2rppn/p3p2p/3pP2Q/3P4/K1PBN2P/PP4P1/R4R2 w - - 0 1 bm Bxh7+ Rf6;
2r2rk1/1bpR1p2/1pq1pQp1/p3P2p/P1PR3P/5N2/2P2PPK/8 w - - 0 1 bm Kg3;
1r4r1/3q1npk/2b1pbnp/Rp1p4/1N1P3P/2PQ1pP1/1K3B2/5B1R w - - 0 1 bm Qxg6+;
2b1rk2/5p2/p1P5/2p2P2/2p5/7B/P7/2KR4 w - - 0 1 bm f6;
4rk2/5p2/p1P2P2/2p5/2p5/7b/P7/2KR4 w - - 0 2 bm c7;
r7/ppK2P1P/8/2P5/3k4/8/P7/8 w - - 0 1 am Kxb7; bm Kd7;
r4rk1/bpp2pp1/p1np1n1p/3Np3/1PP5/P2PPNPq/1BQ2P1P/R4RK1 b - - 0 1 bm Ng4;
r4rk1/bpN2pp1/p1np3p/4p3/1PP3n1/P2PPNPq/1BQ2P1P/R4RK1 b - - 0 2 bm f5;
8/3bkp2/n7/1rN1P3/2R3P1/2R4K/2p5/8 b - - am Nb4; bm Nxc5 Rxc5;
8/7p/5p2/6k1/8/6P1/5PPK/8 w - - 0 1 bm Kh1;
4R3/3p4/KB1P3p/7P/8/p5pP/Pp3npb/1R3nkq w - - 0 1 bm Re3 Re6;
2kr1nr1/pbp1qp2/1p2pn1p/8/3Pp2Q/P1P3N1/2PBBPPP/R3K2R w KQ - 0 1 am O-O; bm Bxh6;
2rr2k1/pp2b1pp/1nb1p3/5p2/1P1B4/P2BPP2/3NK1PP/R6R b - - 0 1 bm e5;
r3r3/5p1p/pR3np1/1p1q4/kP6/P1Q2PPB/2P4P/1K6 w - - 0 1 am Be6; bm Bf1;
8/4R1p1/3P4/8/4pp2/PP3k2/2P2b2/1K6 b - - 0 1 bm Bc5;
8/6p1/3PR3/2b5/4pp2/PP3k2/2P5/1K6 b - - 0 2 bm Bxd6;
rnb4Q/1p5p/p1k5/4p3/4q3/8/PPPR3P/2K5 w - - 0 1 am Qxc8+; bm Qf6;
r3r1k1/1p3pp1/p1bp1b1B/2q1n3/2PN4/1P5P/2BR1QP1/5RK1 w - - 0 1 bm b4;
8/5p2/1ppp4/1k6/5P2/7P/8/5K2 b - - 0 1 am Ka5 Kc5; bm Ka4;
r1b1r1k1/1p1nnpp1/pq1Bp2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 0 1 bm Bc7;
6k1/1bq1bpp1/p6p/2p1pP2/1rP1P1P1/2NQ4/2P4P/K2RR3 b - - 0 1 bm Bd5;
5b2/p2k1p2/P3pP1p/n2pP1p1/1p1P2P1/1P1KBN2/7P/8 w - - 0 1 bm Nxg5;
4r2k/Q5pp/3pN3/1P1P1n2/P4P2/2r4q/6RP/3R2K1 w - - 0 1 am Qd7; bm Qf7 Re1;
1rqr2k1/pb3p2/n4b1p/3PN1p1/2pp4/P5P1/1PQB1PBP/2R1R1K1 w - - 0 1 am Nxc4; bm Nxf7;
2rr2k1/pp1q1bp1/4p2p/2npP3/5N1P/1Q4P1/PP3P2/1BRR2K1 w - - 0 1 bm Rxc5;
r2r2k1/2b1qp1p/b1p3p1/p1p1p3/2P1P3/1PN1BP2/P1Q3PP/R2R2K1 b - - 0 1 bm Rd4;
r1b1r1k1/p3qp1p/1ppp1npb/4n3/1PPBP3/2N2N1P/P1Q1BPP1/3RR1K1 w - - 0 1 bm c5;
r4rk1/1b1n1pb1/3p2p1/1p1Pq1Bp/2p1P3/2P2RNP/1PBQ2P1/5R1K w - - 0 1 bm Nf5 Nxh5;
3Rnk1r/5ppp/4p3/8/PN6/7P/1P2bPP1/6K1 w - - 0 1 bm f3;
r2qk2r/pp3ppp/2p1pn2/4n3/1b6/3P2PP/PPPN1PB1/R1BQK2R b KQkq - 0 1 bm h5;
rnbqnrk1/5ppp/pp1b4/3NpP2/P2N4/8/1PP1B1PP/R1BQ1R1K w - - 0 1 bm f6;
rn1qk2r/pp3ppp/4b3/8/2pP1p2/B4N2/P3Q1PP/R4RK1 w kq - 0 1 bm d5;
r3r1k1/pp1bp2p/1n2q1P1/6b1/1B2B3/5Q2/5PPP/1R3RK1 w - - 0 1 bm Bd2;
r1b1r1k1/p2q1ppp/np2n3/3p1NBQ/8/6PB/P4P1P/1R2R1K1 w - - 0 1 bm Bf6;
r1b1r1k1/p2q1p1p/np2np2/3p1N1Q/8/6PB/P4P1P/1R2R1K1 w - - 0 2 bm Qh6 Rd1;
r1b1r1k1/p2q1p1p/np2nBp1/3p1N1Q/8/6PB/P4P1P/1R2R1K1 w - - 0 2 bm Qh6;
r3k2r/4b2p/p1n3pN/1p1q1p2/5B2/3p1P2/PP4PP/2RQR2K w kq - 0 1 bm Rxc6;
2k3nr/1ppr1qpp/p4p2/3P3b/1b6/4BN1P/PP1N1PP1/2RQR1K1 w - - 0 1 bm Nc4;
5r2/1p4r1/3kp1b1/1Pp1p2p/2PpP3/q2B1PP1/3Q2K1/1R5R b - - 0 1 bm Rxf3;
5r1k/1P4pp/3P1p2/4p3/1P5P/3q2P1/Q2b2K1/B3R3 w - - 0 1 bm Qf7;
2rq1rk1/pb3p1p/1p2pbp1/3p3R/2PP4/PP5R/1B3PPP/3Q1BK1 b - - 0 1 am gxh5; bm dxc4;
r1b2rn1/1ppn3k/p4q1p/3P1p2/1p3Q2/1NNB4/P5PP/4RRK1 w - - 0 1 bm Re6;
8/4kpbn/p1p3p1/Pp2p2p/1P2Pn2/N1P1BP2/5P1P/5BK1 w - - 0 1 bm Nxb5;
2r2rk1/p1q1bpp1/1p6/n2R4/8/P4N2/1B2QPPP/5RK1 w - - 0 1 bm Rh5;
r4rk1/1pp2ppp/8/p2q4/Q7/2P4P/PP2nP1K/RNB2R2 b - - 0 1 bm Ra6;
8/4k3/p2p2p1/P1pPn2p/1pP1P2P/1P1NK1P1/8/8 w - - 0 1 am Nxe5; bm g4;
8/1p3p2/p4kpp/1PPp4/P7/7P/5K1P/8 b - - 0 1 am axb5; bm Ke6 Ke7;
r3rnk1/3qbppp/1p2p1n1/pPppP2N/3P3P/2P2NP1/1P3PK1/R1BQR3 w - - 0 1 bm Bh6;
6k1/1p2q2p/5Qp1/3p2K1/3P1PP1/8/7P/8 b - - 0 1 bm h6+;
8/5R2/2p5/8/7P/1K2b3/P3kp2/8 w - - 0 1 bm Kc2;
4kr2/5p1K/3p1Q2/1p4P1/4P3/1PP5/7b/8 w - - 0 1 bm Kh6;
4kr2/5pK1/3p1Q2/1p4P1/4P3/1PP3b1/8/8 w - - 0 1 bm c4;
3r1rk1/2p1qppp/p1n5/1p1bP1N1/3pNQ2/1P6/PP3PPP/2RR2K1 w - - 0 1 bm Rxc6;
7r/4p1k1/p3Pppp/1p6/3N1R2/3PQ2P/qr4b1/5RK1 w - - 0 1 bm Rxf6;
8/4K2p/6pr/5pk1/1pB2R2/p4PP1/8/8 w - - 0 1 bm Rg4;
8/3R1P2/1ppP1p2/3r4/8/K7/p4k2/8 w - - 0 1 am Kxa2; bm Kb2;
q3nrk1/4bppp/3p4/r3nPP1/4P2P/NpQ1B3/1P4B1/1K1R3R b - - 0 1 bm Nc7;
8/8/7p/3KNN1k/2p4p/8/3P2p1/8 w - - 0 1 bm Kc6;
r3qb1k/1b4p1/p2pr2p/3n4/Pnp1N1N1/6RP/1B3PP1/1B1QR1K1 w - - 0 1 bm Nxh6;
r3qb1k/1b4p1/p2pr2N/3n4/Pn2N3/2p3RP/1B3PP1/1B1QR1K1 w - - 0 2 bm Nf5;
2b1r3/r2ppN2/4Bk2/1p1p1b2/pP1P4/2P3R1/PP3PP1/2K5 w - - 0 1 am Bxd5; bm Bxf5;
2b1r3/r2ppN2/8/1p1p1k2/pP1P4/2P3R1/PP3PP1/2K5 w - - 0 1 bm Nd6+;
2r1k2r/pp1qppbp/6p1/5b2/1nPP4/4PNB1/P4PPP/R2QKB1R w KQk - 0 1 am Kd2; bm Rc1;
r1b2rk1/2q1bppp/p1npp3/1pnB1N2/4P1P1/2N1B3/PPP1QP1P/2KR2R1 b - - 0 1 am exd5 exf5; bm Bb7;
8/Nprr1p1p/1n3Pp1/p2pP1k1/PbpP1R2/6P1/RP4NP/6K1 w - - 0 1 bm h4;
r1q2rk1/p2bb2p/1p1p2p1/2pPp2n/2P1PpP1/3B1P2/PP2QR1P/R1B2NK1 b - - 0 1 bm Bxg4;
8/8/p1p5/3kPp1p/2p2PpP/2r3P1/3R1K2/8 b - - 0 1 am Rd3; bm Ke6;
8/8/p1p5/3kPp1p/2p2PpP/3r2P1/3R1K2/8 w - - 0 2 am Ra2 Rb2 Rc2 Re2; bm Rxd3;
4r3/p1p3kp/Pp6/2b2RP1/3r4/6B1/1P4PP/4R1K1 w - - 0 1 bm Rxc5;
3r2k1/5pp1/2QBp3/pp1nP3/8/3q2P1/PP5P/K1R5 b - - 0 1 bm Kh7;
2rq1rk1/1b1nbppp/p2p1n2/1p2pPB1/4P3/P1N3N1/BPP3PP/R2Q1RK1 b - - 0 1 bm Rxc3;

[Vinvin]

...
Look at first game (first diagram) here : http://www.chessbase.com/newsdetail.asp?newsid=4007

...

Blast from the past.
This position still not easy (sometimes more than 1 minutes with 4 cores) for today :
Rxf7!!
[d]r1b1r1k1/1pBnnpp1/p1q1p2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 2 2

[Hai]

...
Look at first game (first diagram) here : http://www.chessbase.com/newsdetail.asp?newsid=4007

...

Blast from the past.
This position still not easy (sometimes more than 1 minutes with 4 cores) for today :
Rxf7!!
[d]r1b1r1k1/1pBnnpp1/p1q1p2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 2 2

This position is very easy:

LC0 Sergio 40x512
1.Rxf7 Kxf7 2.Nd6+ Kg8 3.Nxe8 Nf5 4.Qg6 Qc3 5.Qxe6+ Kh8 6.Rd1 Qxc2 7.Nxg7 Nxg7 8.Qxh6+ Kg8 9.Bf3 Nf8 10.Be5 Qg6 11.Qh4 Be6 12.Bxb7 Ra7
+/- (0.87) depth: 9 00:00:01 746N


And later:
1.Rxf7 Kxf7 2.Nd6+ Kg8 3.Nxe8 Nf5 4.Qg6 Qc3 5.Qxe6+ Kh8 6.Qxf5 Qxd2 7.Qf7 Qe1+ 8.Bf1 Qa1 9.Bd6 Kh7 10.h3 b5 11.Kh2 Nc5 12.Bxc5 Qe5+ 13.Kh1 Bf5 14.Nxg7 Bg6 15.Qb7 Be4 16.Bd3 Bxd3 17.Nf5+ Kg6 18.Nh4+ Kf6 19.Qc6+ Kf7 20.cxd3 Qe1+ 21.Bg1
+- (2.09) depth: 21/44 00:01:14 598kN

[MikeB]

...
Look at first game (first diagram) here : http://www.chessbase.com/newsdetail.asp?newsid=4007

...

Blast from the past.
This position still not easy (sometimes more than 1 minutes with 4 cores) for today :
Rxf7!!
[d]r1b1r1k1/1pBnnpp1/p1q1p2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 2 2

Honey-XI-LP ( LP = Large Pages enabled - about 10% faster, coming soon)

r1b1r1k1/1pBnnpp1/p1q1p2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 2 2

+5.22

Code: Select all

dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
 49	+5.22!	48.0G	7:29.42	Rxf7!
 49	+5.09!	42.2G	6:35.41	Rxf7!
 48	+4.95 	39.2G	6:07.86	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Kxf8 Bh5 Be6 Bxe8 Rxe8 Qxb7 Kg8 Qxa6 Kh7 Qc6 Bf7 Rd7 Bg6 g4 Ne3 Qf6 Rg8 Qxe5 Nxg4 Qd4 h5 c4 Kh8 Ra7 Nf6 Qd6 Bf5 Kg1 Be4 c5 Rc8 Rf7 Bg6 Re7 Re8 Rxe8+ Bxe8 c6 Bxc6 Qxc6 Kh7 
 48	+5.08!	37.5G	5:51.87	Rxf7!
 47	+4.94 	27.3G	4:16.66	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Kxf8 Bh5 Be6 Bxe8 Rxe8 Qxb7 h5 Qe4 Re7 Qxe5 Bd7 Qc5 Ke8 Kg1 Re1+ Kf2 Re7 Qa5 Nh6 Qxh5+ Kf8 h3 Ng8 Qc5 Ke8 Rd6 Nf6 Kg1 Re1+ Kh2 Re6 Rxe6+ Bxe6 Qd6 Kf7 Qxa6 g5 g4 Bd7 Qd6 Kg
 46	+5.03 	27.2G	4:15.63	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf6 Bb2 b5 Bxf6 gxf6 Qc7 Re7 Rd8+ Kh7 Qc5 Bb7 Bd3 Bxg2+ Kg1 Be4 Qxe7+ Nxe7 Bxe4+ f5 Rxa8 Kg6 Bd3 Nd5 Rxa6 Kf6 Kf2 Nc7 Ra7 Nd5 Bxb5 Kg5 c4 Nf6 Ra6 Kf4 Rxe6 Ne4+ Kg2 h5 Bc6 Nd2 Bd5 Nb3 Rh6 
 45	+4.90 	22.9G	3:35.69	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf6 Bb2 e5 Bxe5 Be6 Bxf6 gxf6 g4 Ng7 Qxf6 b5 Qxh6 Bf7 Qg5 Ra7 Bd3 Rae7 Kg1 Bc4 Bg6 Bf7 Bf5 Re2 Rd6 Re1+ Kf2 R1e2+ Kg3 R8e3+ Kf4 Re5 Rxa6 Rxf5+ gxf5 Rf2+ Ke3 Rxf5 Qe7 Kh7 Qe4 Bg6 Qg2 Bf7 R
 45	+4.89!	21.3G	3:20.57	Rxf7!
 45	+4.76?	21.1G	3:18.71	Rxf7 Kxf7?
 44	+4.89 	19.9G	3:07.48	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Rxf8 Qxe5 Kh7 g4 Kh8 Bd3 Bd7 Bxf5 Rae8 Qa5 Bxf5 gxf5 b5 Rd5 Ra8 Qc7 Rac8 Qe7 Rce8 Qd6 Re1+ Kg2 Rf6 Qc7 Re2+ Kg3 Re8 Rd7 Rg8 Qe5 Ra8 Kh3 Rc8 Ra7 b4 Kg3 Rc3+ Kf4 Rc4+ Ke3 Rc
 43	+4.82 	17.5G	2:45.58	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Kxf8 Bh5 Be6 Bxe8 Rxe8 Qxb7 Kg8 Qxa6 Kh7 Qc6 Bf7 Rd7 Bg6 g4 Ne3 Qf6 Rg8 Qxe5 Nxg4 Qd4 Bf5 Rf7 Bc8 h3 Kg6 Ra7 Nf6 Kh2 Bf5 c4 h5 Qf4 h4 Qxh4 Nh5 Ra5 Rf8 Re5 Rf6 c5 Re6 Rxf5 
 43	+4.81!	17.1G	2:42.10	Rxf7!
 43	+4.67!	14.5G	2:17.39	Rxf7!
 42	+4.54 	10.5G	1:39.64	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf6 Bb2 b5 Bxf6 gxf6 Qc7 Re7 Rd8+ Kh7 Qc5 Bb7 Bd3 Bxg2+ Kg1 Be4 Qxe7+ Nxe7 Bxe4+ Kg7 Rxa8 a5 Rxa5 b4 Ra6 Kf7 Rb6 f5 Bf3 Kf6 Rxb4 Ke5 Kf2 Ng8 Ke3 Nf6 Rb5+ Kd6 c4 Nd7 Kd4 e5+ Ke3 Kc7 Bd5 Kd
 42	+4.41!	8.31G	1:19.54	Rxf7!
 42	+4.28?	8.10G	1:17.61	Rxf7 Kxf7?
 41	+4.41 	7.70G	1:13.80	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Rxf8 Qxe5 Kh7 g4 Kh8 Bd3 Bd7 Bxf5 Bxf5 gxf5 Rae8 Qa5 b5 Rd5 Rc8 Qa3 Kg8 Qxa6 Rxc2 Qe6+ Kh8 Qe5 Rc4 Rxb5 Rc1+ Kg2 Rc6 Rb7 Rcf6 Kh3 Rc8 Qe7 Rg8 Qd7 Rff8 Qb5 Rf6 Kg3 Kh7 Qd7 
 40	+4.32 	6.43G	1:01.84	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Rxf8 Qxe5 Kh7 g4 Kh8 Bd3 Bd7 Bxf5 Bxf5 gxf5 Rae8 Qa5 b5 Rd5 Rc8 Qa3 Kg8 Qxa6 Rxc2 Qe6+ Kh8 Qe5 Rc6 Rxb5 Rcf6 Rb7 Kg8 Qd5+ Kh7 Qd7 Rg8 Kg2 Rff8 Qe6 Kh8 Qe5 Rf6 Kh3 Rff8 Kg4
 40	+4.25!	5.93G	0:57.07	Rxf7!
 40	+4.13?	5.82G	0:56.04	Rxf7 Kxf7?
 39	+4.25 	5.27G	0:50.75	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf6 Bb2 b5 Bxf6 gxf6 Qc7 Re7 Rd8+ Kh7 Qc5 Bb7 Bd3 Bxg2+ Kg1 Be4 Qxe7+ Nxe7 Bxe4+ f5 Bxa8 Kg6 Rd6 Kf7 Rxa6 Ng6 Kf2 Ne5 Bf3 Nc4 Bc6 Nd6 Rb6 Nc8 Rxb5 Ke7 Bf3 Nd6 Rb6 Nc4 Ra6 Nd6 Ke3 Nf7 Rb6 
 39	+4.13!	4.51G	0:43.57	Rxf7!
 39	+4.00?	4.33G	0:41.91	Rxf7 Kxf7?
 38	+4.13 	4.28G	0:41.42	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Kxf8 Bh5 Be6 Bxe8 Rxe8 Qxb7 Bc8 Qc7 h5 Re2 Kg8 Rxe5 Rxe5 Qxe5 Kf7 c4 h4 Qc7+ Ne7 Qf4+ Nf5 c5 Kf6 Qc7 Be6 c6 g5 Qd8+ Ne7 Qf8+ Bf7 c7 a5 c8=Q Nxc8
 38	+4.12!	4.02G	0:38.90	Rxf7!
 38	+3.99!	3.60G	0:34.91	Rxf7!
 37	+3.87 	2.71G	0:26.44	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf6 Bb2 b5 Bxf6 gxf6 Qc7 Re7 Rd8+ Kh7 Qc5 Bb7 Bd3 Bxg2+ Kg1 Be4 Qxe7+ Nxe7 Bxe4+ f5 Bxa8 Kg7 Rd6 Kf6 Rxa6 Ng6 Kf2 h5 Bf3 h4 Rb6 Ke5 Ke3 Kf6 Bd5 Nf8 Bc6 b4 Rxb4 h3 Rb6 Nh7 c4 Ke5 Rb5+ Kf6 
 37	+3.76!	2.49G	0:24.33	Rxf7!
 37	+3.65!	2.42G	0:23.61	Rxf7!
 36	+3.64!	2.01G	0:19.67	Rxf7!
 36	+3.53!	1.78G	0:17.44	Rxf7!
 35	+3.42 	1.47G	0:14.44	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Rxf8 Qxe5 Kh7 g4 Kh8 Bd3 Bd7 Bxf5 Rae8 Qc5 Bxf5 gxf5 Rf7 Kg2 Ref8 Rf2 Rf6 Qe5 Kh7 h4 g6 fxg6+ Rxg6+ Kf1 Rxf2+ Kxf2 Rc6 Ke3 Kg6
 35	+3.23!	1.34G	0:13.18	Rxf7!
 35	+3.03!	1.21G	0:11.93	Rxf7!
 35	+2.89!	1.15G	0:11.39	Rxf7!
 35	+2.78!	1.13G	0:11.13	Rxf7!
 34	+2.68 	939.9M	0:09.29	Rxf7 Kxf7 Nd6+ Qxd6 Bxd6 Nf5 Qf4 Kg8 Ba3 Nf8 Qc7 e5 Bxf8 Rxf8 Qxe5 h5 Bxh5 a5 Rf2 a4 g4 a3 gxf5 a2 Rf1 Bxf5 Rg1 Be4+ Qxe4 a1=Q Rxa1 Rxa1+ Kg2 Raf1 Bg6 R1f2+ Kg3 R8f3+ Qxf3 Rxf3+ Kxf3 Kf8 Ke4 b5 c3 Ke7 Ke5 Kd7 Be4
 34	+2.26!	875.3M	0:08.63	Rxf7!
 34	+1.73!	872.3M	0:08.60	Rxf7!
 34	+1.32!	869.1M	0:08.56	Rxf7!
 34	+1.00!	865.4M	0:08.53	Rxf7!
 34	+0.76!	862.7M	0:08.50	Rxf7!
 34	+0.58!	814.1M	0:08.00	Rxf7!
 34	+0.44!	808.3M	0:07.95	Rxf7!
 34	+0.34!	806.1M	0:07.92	Rxf7!
 34	+0.28!	803.0M	0:07.89	Rxf7!
 33	+0.21 	649.7M	0:06.39	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Rf8 Rxf8+ Nxf8 Bd8 b5 Be7 Bb7 h4 Qc7 Rf2 Qxe7 Rf7 Qxf7 Nxf7 Kxf7 Qc7+ Kf6 Qxb7 Rd8 Qxa6 Rd5 g4 Nd7 Qa1+ Kf7 Qa7 Ke7 Qa3+ Kf7 Kg2 Rc5 Kh3 Rc4 Qf3+ Ke7 g5 hxg5 hxg5 Rc5 Qa3 Kf7 Qe3 Ke7 Qd2 Rf5 Qb4
 32	+0.26 	479.0M	0:04.73	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Rf8 Rxf8+ Nxf8 Bd8 b5 Be7 Bb7 h4 Qc7 Rf2 Qxe7 Rf7 Qxf7 Nxf7 Kxf7 Qc7+ Kf6 Qxb7 Rd8 Qxa6 Rd5 Qa1+ Kf7 Qa7+ Nd7 g4 Ke7 Qa3+ Kf7 Kh2 Rc5 Qf3+ Kg8 Kh3 Nf6 Qe3 Rc6 h5 Kf8 Qe2 Kf7 Qxb5 Rxc2 Qb7+ Kf8 Q
 32	+0.33?	433.1M	0:04.29	Bh5 Nf5?
 31	+0.39!	368.9M	0:03.67	Bh5!
 31	+0.29!	344.2M	0:03.43	Bh5!
 31	+0.23?	339.4M	0:03.39	Bh5 Nf5?
 30	+0.29 	281.1M	0:02.82	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Rf8 Rxf8+ Nxf8 Bd8 b5 Be7 Bb7 h4 Qc7 Rf2 Qxe7 Rf7 Qxf7 Nxf7 Kh7 Qd6 Bd5 Nd8 Kg8 Qe7 e5 Qd6 Ba2 Nc6 Re8 Nxe5 Re6 Qb8 Kh7 h5
 29	+0.22 	182.1M	0:01.84	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Re7 Bd8 exf5 Bxe7 Kh7 Re2 Qd5 Re1 b5 Ne8 Qd4 Bf6 Qg4 Bxg7 Qxg3 hxg3 Nb6 Bd4 Nd5 Nd6 Bd7 Re5 Bc6 Rxf5 Rg8 Rf7+ Kg6 Ra7 Kh5 Rxa6 Nb4 Rb6 Nxc2 Bc5 Bd5 Rxb5 Kg6 Bb6
 28	+0.14 	169.8M	0:01.72	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Re7 Bd8 exf5 Bxe7 Kh7 Re2 Qd5 Re1 b5 Ne8 Qd4 Bf6 Qg4 Bxg7 Qxg3 hxg3 Nb6 Bd4 Nd5 Nd6 Bd7 Re5 Bc6 Rxf5 Rg8 Rf7+ Kg6 g4 b4 Ra7 Ba4 Kh2 Bxc2 Rxa6 Bd3
 27	+0.12 	168.3M	0:01.70	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Re7 Bd8 exf5 Bxe7 Kh7 Re2 Qd5 Re1 b5 Ne8 Qd4 Bf6 Qg4 Bxg7 Qxg3 hxg3 Nb6 Bd4 Nd5 Nd6 Bd7 Re5 Bc6 Rxf5 Rg8 Rf7+ Kg6 Kh2 b4 Ra7 Ba4 Rxa6 Bxc2 g4 Nc7 Rb6 Nd5 Rb7 Nf6
 26	+0.15 	143.3M	0:01.45	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Re7 Bd8 exf5 Bxe7 Kh7 Re2 Qd5 h3 f4 Qc3 f3 gxf3 b5 Rg2 Ne5 Nxc8 Qd1+ Rg1 Qxf3+ Qxf3 Nxf3 Rg3 Rxc8 Rxf3 Rxc2 Ra3 Rc7 Bf8 Rc8 Bb4 Rc4 Rb3 g5 Kh2 h5 Be7 g4 Kg3 gxh3
 25	+0.30 	96.9M  	0:00.99	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Re7 Bd8 exf5 Bxe7 Kh7 Re2 Qd5 h3 f4 Qc3 Qh5 Qd3+ Kh8 Nxc8 f3 Rd2 Ne5 Qc3 Nc6 Nb6 Re8 Bc5 Re2 Rxe2 fxe2 Bf2 Qe8 Kh2 Qe4 Nc4 Qf4+ Kg1
 24	  0.00 	91.9M  	0:00.94	Bh5 Nf5 Bxf7+ Kxf7 Rxf5+ exf5 Nd6+ Qxd6 Bxd6 Nf6 Qb3+ Kg6 Qg3+ Kf7
 23	  0.00 	79.9M  	0:00.82	Bh5 Nf5 Bxf7+ Kxf7 Nd6+ Kg8 Rxf5 Re7 Bd8 exf5 Bxe7 Kh7 Re2 Qd5 h3 f4 Qc3 Qh5 Qd3+ Qg6 Qd5 Nb6 Qd4 f3 gxf3 Qg3 Qd3+ Qg6 Qd4
 22	+0.04 	57.5M  	0:00.59	Bh5 Nf5 Bxf7+ Kxf7 Rxf5+ exf5 Nd6+ Qxd6 Bxd6 Nf6 Be5 Be6 Qf3 Rad8 Qxb7+ Re7 Qb4 Rxd2 Qxd2 Rd7 Qe1 Ng4 Kg1 Nxe5 Qxe5 Rd1+ Kf2 Rd2+ Kg3
 21	  0.00 	53.4M  	0:00.55	Nd6 Rf8 Bd8 Ng6 Bh5 Qc5 Bxg6 fxg6 Rxf8+ Nxf8 Qf4 Bd7 Qf7+ Kh8 Qxf8+ Kh7 h3 Bc6 Re2 Bd7 Rd2
 20	+0.03 	39.3M  	0:00.41	Nd6 Rf8 Bd8 Ng6 Bh5 Qc5 Bxg6 fxg6 Rxf8+ Nxf8 Qf3 Bd7 Be7 Nh7 Qf7+ Kh8 Qxg6 Be8 Qxe6 Qc3 Rd1 Bh5 Nf7+ Bxf7 Qxf7 Qxc2 Rf1
 19	+0.20 	19.0M  	0:00.20	Nd6 Rf8 Ba5 Qc5 Bc3 Qg5 Nxc8 Raxc8 Qxg5 hxg5 Rxd7 Rxc3 Rxe7 Rxc2 Bg4 b5 Ra7 f5 Bd1 Rc6 Bf3
 18	+0.23 	12.3M  	0:00.13	Nd6 Rf8 Bd8 Ng6 Bh5 Nde5 Nxf7 Rxf7 Rxf7 Kxf7 Qxe5 Qb5 Qxb5 axb5 h3 Ra1+ Kh2 Rf1 g4 b6 Kg2 Ra1 Rf2+ Ke8 Bc7 Bb7+ Kg3 Ra3+ Kh2
 17	+0.16 	11.1M  	0:00.12	Nd6 Rf8 Bd8 Ng6 Rxf7 Rxf7 Qxg6 Rf2 Qxe6+ Kh8 Nf7+ Rxf7 Qxf7 Ne5 Qf8+ Kh7 Bh4 b5 Bg3 Bh3 Qf2 Re8 Bh5 Re6 Qg1 Ng6 Bxg6+ Rxg6 Rd8
 16	+1.64 	4.16M  	0:00.05	Nd6 Qxc7 Qxg7+ Kxg7 Nxe8+ Kg8 Nxc7 Ra7 Bh5 f5 Nxe6 Nf6 Rd8+ Kh7 Re1 Ne4 Nd4 b6 Bf3 Rd7 Rxd7 Bxd7 Nxf5 Bxf5 Bxe4
 15	+1.59 	3.67M  	0:00.04	Nd6 Qxc7 Qxg7+ Kxg7 Nxe8+ Kg8 Nxc7 Ra7 Bh5 f5 Nxe6 Nf6 Rd8+ Kh7 Bf7 Bxe6 Bxe6 b5 Re1
 14	+1.61 	2.17M  	0:00.03	Nd6 Qxc7 Qxg7+ Kxg7 Nxe8+ Kg6 Nxc7 Rb8 Rd3 Nf5 g4 Ne7 Rdf3
 13	+1.13 	1.88M  	0:00.02	Nd6 Qxc7 Qxg7+ Kxg7 Nxe8+ Kg8 Nxc7 Rb8 Bh5 Nf5 g4
 12	+0.81 	943374	0:00.01	Bh5 Rf8 Bd6 Nf5 Qf4 Rd8 Be7 g6 Bxd8 gxh5
 11	+0.42 	592019	0:00.01	Nd6 Rf8 Bd8 Ng6 Bh5 Qa4 Bxg6
 10	  0.00 	465808	0:00.01	Bh5 Rf8 Bd6 Nf5 Qf4 Rd8 Bc7 Rf8
  9	+0.58 	191434	0:00.00	Rxf7 Kxf7 Nd6+ Kg8 Nxe8 Nf5 Qg6 Kh8
  8	+0.61 	138621	0:00.00	Rxf7 Kxf7 Nd6+ Kg8 Nxe8 g5 c4
  7	+0.05 	112998	0:00.00	Be5 Nxe5 Nf6+ Kh8 Nxe8 Qxe8 Qxe5
  6	+0.14 	80472  	0:00.00	Be5 Nxe5 Nf6+ Kh8 Nxe8 Qxe8 Qxe5
  5	+0.51 	66764  	0:00.00	Be5 Nxe5 Nf6+ Kh8 Nxe8 Qxe8
  4	+0.45 	61662  	0:00.00	Be5 Nxe5 Nf6+ Kf8
  3	 -0.05 	53336  	0:00.00	Be5 Nxe5 Nf6+ Kf8 Nxe8
  2	+0.29 	43287  	0:00.00	Be5 Nxe5
  1	+2.54 	16897  	0:00.00	Bh5 Qxe4 Rxf7
  0	#

[M ANSARI]

Nice positions! Thanks for posting that.

[zullil]

...
Look at first game (first diagram) here : http://www.chessbase.com/newsdetail.asp?newsid=4007

...

Blast from the past.
This position still not easy (sometimes more than 1 minutes with 4 cores) for today :
Rxf7!!
[d]r1b1r1k1/1pBnnpp1/p1q1p2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 2 2

This position is very easy:

LC0 Sergio 40x512
1.Rxf7 Kxf7 2.Nd6+ Kg8 3.Nxe8 Nf5 4.Qg6 Qc3 5.Qxe6+ Kh8 6.Rd1 Qxc2 7.Nxg7 Nxg7 8.Qxh6+ Kg8 9.Bf3 Nf8 10.Be5 Qg6 11.Qh4 Be6 12.Bxb7 Ra7
+/- (0.87) depth: 9 00:00:01 746N


And later:
1.Rxf7 Kxf7 2.Nd6+ Kg8 3.Nxe8 Nf5 4.Qg6 Qc3 5.Qxe6+ Kh8 6.Qxf5 Qxd2 7.Qf7 Qe1+ 8.Bf1 Qa1 9.Bd6 Kh7 10.h3 b5 11.Kh2 Nc5 12.Bxc5 Qe5+ 13.Kh1 Bf5 14.Nxg7 Bg6 15.Qb7 Be4 16.Bd3 Bxd3 17.Nf5+ Kg6 18.Nh4+ Kf6 19.Qc6+ Kf7 20.cxd3 Qe1+ 21.Bg1
+- (2.09) depth: 21/44 00:01:14 598kN

And in between, the engine switches to Nd6.

[jp]

And in between, the engine switches to Nd6.

And is Nd6 clearly bad?

[Hai]

...
Look at first game (first diagram) here : http://www.chessbase.com/newsdetail.asp?newsid=4007

...

Blast from the past.
This position still not easy (sometimes more than 1 minutes with 4 cores) for today :
Rxf7!!
[d]r1b1r1k1/1pBnnpp1/p1q1p2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 2 2

This position is very easy:

LC0 Sergio 40x512
1.Rxf7 Kxf7 2.Nd6+ Kg8 3.Nxe8 Nf5 4.Qg6 Qc3 5.Qxe6+ Kh8 6.Rd1 Qxc2 7.Nxg7 Nxg7 8.Qxh6+ Kg8 9.Bf3 Nf8 10.Be5 Qg6 11.Qh4 Be6 12.Bxb7 Ra7
+/- (0.87) depth: 9 00:00:01 746N


And later:
1.Rxf7 Kxf7 2.Nd6+ Kg8 3.Nxe8 Nf5 4.Qg6 Qc3 5.Qxe6+ Kh8 6.Qxf5 Qxd2 7.Qf7 Qe1+ 8.Bf1 Qa1 9.Bd6 Kh7 10.h3 b5 11.Kh2 Nc5 12.Bxc5 Qe5+ 13.Kh1 Bf5 14.Nxg7 Bg6 15.Qb7 Be4 16.Bd3 Bxd3 17.Nf5+ Kg6 18.Nh4+ Kf6 19.Qc6+ Kf7 20.cxd3 Qe1+ 21.Bg1
+- (2.09) depth: 21/44 00:01:14 598kN

And in between, the engine switches to Nd6.

Maybe you are using the wrong net or your GPUs are to weak.
Running on my pc it doesn't switched and I have let it run up to depth 25.
I'm sure it doesn't switched up to depth 21 and later to switch to Nd6 and back to Rxf7 doesn't make sense, because Nd6 needs to have better evaluation than +2.09, after 1:14 minutes as you can see.

[jd1]

Play 1.Rb1! that draws. Other moves lose.

[d]1R6/8/8/5bp1/4p2k/8/B1p2PKP/8 w - - 0 1
Could you please check this one? I believe 1. Rb1 cxb1Q 2. Bxb1 e3! wins for Black.