OpenChess

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nTCEC Season 1 – Stage 2b starts March 11th at 14:00 UTC+1.

Stage 2b is a double Round Robin consisting of 8 chess engines, with a total of 56 games.
Each pair will play both sides of the openings.

The top 4 will move on to Stage 3, while those finishing 5-8 are out of nTCEC for the current Season.
Stage 3 will start 2-3 days after Stage 2b is finished.

The list of participants for Stage 2b:
Vitruvius, Gull, Chiron, Komodo, Shredder, Scorpio, Quazar, Hannibal

nTCEC is using 150m + 60s per move for the whole game, running on an Intel Core i7 3770k @ 4500 MHz.
Up to 3 cores can be used for engines capable of SMP.

Houdini, Rybka, Hiarcs and Stockfish already qualified for Stage 3 after finishing 1-4 in Stage 2a that finished a few days ago.

Read the full nTCEC rules here:
http://www.tcec-chess.net/viewtopic.php?f=13&t=20

The broadcast will be running 24/7 with 1 game at a time, and can be watched here, also with chat:
http://www.tcec-chess.net/live.php

Finished games from Stage 2b will be moved here:
http://www.tcec-chess.net/stage_2b.php

Read the latest nTCEC news here:
http://www.tcec-chess.net/viewforum.php?f=2

Hope to see everyone there!

Best Regards,
Martin Thoresen

Now live!

http://www.tcec-chess.net/live.php

Standings after 2 of 14 rounds:

Vitruvius-Hannibal, a draw nearly from the start it seemed.
Gull-Quazar, White eventually broke through in the R vs B endgame. Maybe Bb3 on move 93 is inaccurate. White's Kxf6 on move 98 is probably not as good as Kg6. On Black's 100th move, I like Kxd4 over a3. This seems to draw. Both engines liked a3, but I don't see why.
Chiron-Scorpio, eventually White's grip on d6 won the day. Maybe something like Qb2 rather than Bb5 on move 25 offers more hope, though the White4 K-side pressure is building.
Komodo-Shredder, Black failed to recapture the c-pawn, and it turned into a passed monster. After it was captured, White had another c-passer. Shredder had high scores for a few moves, but I don't think it is really all that bad in the immediate future. The endgame perhaps has more chances to draw for Black than it looks, but I think White should win. [In the Rook endgame, White's pieces are much more active, in addition to the extra pawn].

Gull-Hannibal, I think the easiest thing to say is that Black never equalised. White had the space advantage, Black was cramped, and 1-0 resulted via a pawn-up endgame. Gull thinks Rc8 (move 31) by Black was inexact, and I tend to agree, but White is always going to have good winning chances.
Chiron-Vitruvius, this was a fairly wild game, White had Q+2N+abgh to Q+2B+fgh (first with rooks for each side), and as time went by, White's King lacked safety. Maybe White should have tried trading queens, as all the Black pawns were on one side of the board, possibly favouring the Knights, I don't know (the Knights were also over the Q-side, so maybe that was a problem). Eventually both the g-h pawns of White fell, and Black won.
Komodo-Quazar (both single cpu), shows that TBs have at least some effect, as Quazar was showing +4 in a drawn Q vs RP(P) endgame. White had a decent advantage until Black took over the h-file, and the g-pawn(s) became dangerous. After Black's last pawn went, it was QBN vs RNNPP(P), and the b-c pawns were sufficiently advanced for it to become a draw.
Shredder-Scorpio, Black made more small errors than White to move 20 or so, particularly with his Queen being chased around and e6 being weak. White's nice Nxd4 (giving up the Queen for pieces) gave it a winning advantage.

Chiron-Hannibal, it seemed as though White had an edge, particularly after the Queen trade (move 52), but the passed d-pawn never went anywhere, and Black was able to draw.
Komodo-Gull, another game where tablebases would have shortened the game a lot. Komodo was showing as high as +0.92 around move 55, but looks this to me to be at most a very minimal White edge.
Shredder-Vitruvius, White had an eval spike with Qf6, but Black's defenses were sufficient. It was the kind of position that one could not be sure there was some short just beyond the horizon, even with search depths at 20-25 ply (somewhat against the idea of "tactical sufficiency" that was championed about some years ago). The Bg6 defense by Black was quite nice too, with the Nh4 hanging, and in some lines White could win a piece, but be powerless against Black (with Queen on f2) playing Rd8-b8-b2 with a perpetual ensuing.
Scorpio-Quazar, another one that lasted awhile, with the last 100 moves or so being rather futile it seems. White's eval reached 2.57 at move 72, but I think 0.5 is probably a closer reality. Almost all the endgames here should be drawn I think.

Standings after 4 of 14 rounds: Finished games:
http://www.tcec-chess.net/stage_2b.php

Standings after 6 of 14 rounds:
Finished games:
http://www.tcec-chess.net/stage_2b.php

Komodo-Hannibal, once Rxc6 got played, the pawns were worth more than the exchange, especially when White got 2 passed pawns in the centre. Komodo seems to be good at evaluating this type of imbalance.
Shredder-Chiron, I'm not sure whether QBB is better than RRBB theoretrically or not. It must depend on the king safety, and here Black's was not that great. It seems that Bd6 (move 36) was the move that tipped the balance.
Scorpio-Gull, with the queen exchange on move 10, this looks very drawish. Nxf2 gets another 2 pieces off the board, and White can't really claim much of an advantage. Maybe a slight temporary development edge, but no way to cause a weakness via it.
Quazar-Vitruvius, the former was optimistic as usual, but White's attack was never really that dangerous. The edge tipped to Black after the a-file was opened (this makes sense, as Black's king is safer), perhaps because Quazar made moves to try to keep its "edge", but the ending was drawn, as White's Queen eventually became annoying too.

Shredder-Hannibal, White seemed to have an edge, but lost its way in a tactical line around move 20, and Black equalised.
Scorpio-Komodo, a Keres Attack Sicilian, which is supposed to give White a good edge, but here Black blunted White's offensive, and was able to get Q-side play with a knight sacrifice (move 23). After a few more exhcnages, Black had a couple of pawns for the exchange, with a better position, as White only had one pawn left, with no place for its King with major pieces floating about. In the end, this proved the difference, as Black was able to create enough threats to win.
Quazar-Chiron, again the former liked its position by more than is probably correct, with all the ensuing major piece endings essentially drawn.
Vitruvius-Gull, White eventually got the pawn storm going with f4/g4/h4, and after a few more preparations, was able to break through on the K-side.

Scorpio-Hannibal was a reasonably interesting draw. Black played e5 in a Sicilian, and eventually d5 was the spot of exchanges that gave White BN for RP. However, the central pawns were all gone, and the Rook had good mobility while the Knight was too slow -- thus the usual 2 versus 1 potential for the BN never materialised, and Black had a fairly easy draw in the end.
Quazar-Shredder, the former showed large scores as usual, and this time was correct. The opening practically gave White a g4/h4 smother attack, and it worked. Black's h5 was a nice move to slow down the momentum, but as White had a Maroczy bind structure, Black could never break anywhere, and was essentially doomed. After much shuffling, finally White got Reg2 in (move 40), and it was over. Maybe Black should play something like Kh7 (allowing Nxe4) on move 39.
Vitruvius-Komodo, again there was a pawn storm on the Black King, with White eventually ending up with g7/h6 passers(!). This seemed to be tricky to evaluate, especially in the ensuing rook(s) endgame, when Black can just shuffle Kh7-g8. There were two points where White perhaps had better chances, firstly after Nxf6+ on move 35 rather than Ka2 (though again Black has drawing chances I feel), and secondly after Black played Rg8 on move 38 (this looks dubious itself), when instead of b4 it seems that Kb3/Ka3 and White will clear out the Q-side. The idea being that Black is essentially zugwanged (which would not be true if Kg8 were played instead of Rg8, as then Black can shuffle the 8th rank rook, though again for Black to hold will take some work).
Gull-Chiron, White's play out of the opening netted a piece for a couple of pawns. I'm not too sure where Black went wrong in that sequence, but I think White should win after that.

Quazar-Hannibal, unsurprisingly the former claimed an edge when Black saw it as drawish. Both seem to be correct, as I think it is drawish (around move 30), but White won in the end. White's kingside pawns (particularly the f6 pawn) formed a kind of a net for the Black king in many lines. Black should probably play more actively, for instance Ra2+ at some point, and/or not allow f6.
Vitruvius-Scorpio, White saw an edge with a passed pawn upon a5 on move 28, and Black then agreed. Black was actually searching deeper here (and Vitruvius was as usual making almost half of its moves instantly), so I am more inclined to think it was passed pawn eval (or extensions) rather than being outsearched.
Gull-Shredder, I don't think White got much out of the opening. Once Black gets the Knight to d5, things should be OK, and I really don't see anything better than e5 on move 9. Both sides ended up castling Q-side, but nothing really ever happened.
Chiron-Komodo, Black immediately doubled White's c-pawns via Bxc3 in an e6/Bb4 Sicilian. This gives White two bishops, but their attacking potential never materialised. By move 20 Black had at least equalised, and then the minor pieces mostly disappeared. The passed d6-pawn was not a real worry (blockaded by the Bd7), though it did mean that Black was never able to play for more than a draw.

Standings after 9 of 14 rounds: Finished games:
http://www.tcec-chess.net/stage_2b.php

Standings after 11 of 14 rounds: Finished games:
http://www.tcec-chess.net/stage_2b.php

Looks like it came down to Hannibal-Quazar for the last qualification spot, White needing to win. The opening was decent, and Hannibal had a reasonable edge, but Quazar was able to head to a drawable endgame. [After Nxb3, White's main edge is development and space, and if it goes to an endgame, Black should be OK, I think]. White had an extra exchange, but no passed pawns, and in R vs B this usually is not enough. Vitruvius should remain undefeated it seems. The opening selection (always a gripe it seems) had more 2-0 White results than previously (only Critter/Houdini and Spike/Gaviota in Stage 2a, neither a "clear" White edge), and some of them almost seemed to be fairly "routine" attacks to me. But as I say, the openings will always engender complaints.