Search found 8339 matches

by Dann Corbit
Sat Oct 05, 2019 4:03 am
Forum: Computer Chess Club: General Topics
Topic: what is the best engine for big material handicap?
Replies: 57
Views: 4551

Re: what is the best engine for big material handicap?

I analyzed this one before. It is a loss in 15 moves: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/4K3 w kq - acd 31; acs 7920; bm c3; ce -32737; dm -15; pm c3; pv c3 e5 g3 d5 f3 Qf6 g4 Qh4+ Kd1 Qxh2 g5 Qh1+ Kc2 Qg2 e4 dxe4 b4 exf3 a3 Be6 c4 Bf5+ Kb3 Qxd2 Ka4 Qd1+ Kb5 Bd7+ Ka5 b6+; I think it may have been on...
by Dann Corbit
Sat Oct 05, 2019 2:44 am
Forum: Computer Chess Club: General Topics
Topic: Nolot #3 vs. SF Dev
Replies: 4
Views: 486

Re: Nolot #3 vs. SF Dev

OK, it makes sense now. Your current position is wrong. The position you provided has no castle rights. Nolot #3 has castle rights in the position: See: https://en.wikipedia.org/wiki/Nolot Problem 3 FEN: r2qk2r/ppp1b1pp/2n1p3/3pP1n1/3P2b1/2PB1NN1/PP4PP/R1BQK2R w KQkq - 0 1 Problem 3 Smagin - Sahovic...
by Dann Corbit
Sat Oct 05, 2019 2:41 am
Forum: Computer Chess Club: General Topics
Topic: Nolot #3 vs. SF Dev
Replies: 4
Views: 486

Re: Nolot #3 vs. SF Dev

Hold on again, I had the wrong castle rights.
I will try again with castle rights set to none
by Dann Corbit
Sat Oct 05, 2019 2:25 am
Forum: Computer Chess Club: General Topics
Topic: Nolot #3 vs. SF Dev
Replies: 4
Views: 486

Re: Nolot #3 vs. SF Dev

Are you sure that Nxg5 is better than (for instance) h3? Edit: My bleeding edge SF solved it pretty quickly: Searching: r2qk2r/ppp1b1pp/2n1p3/3pP1n1/3P2b1/2PB1NN1/PP4PP/R1BQK2R w KQkq - 0 1 infinite: 0 time: 0 increment: 0 moves to go: 0 1 +1.48 00:00 7877 O-O Bxf3 Rxf3 2 +1.67 00:00 32607 O-O Nxf3+...
by Dann Corbit
Fri Oct 04, 2019 7:29 pm
Forum: Computer Chess Club: General Topics
Topic: Can YOU compile this engine?
Replies: 8
Views: 1021

Re: Can YOU compile this engine?

I gave it a shot, but it is harder than you might think. Something naive like this does not work: #if defined(_M_ARM64) #include "arm64_neon.h" #include "arm64intr.h" typedef _n64 Bitboard; inline int popcount(Bitboard b) { return neon_cnt(b); } #undef USE_PEXT #define USE_POPCNT #else ... because i...
by Dann Corbit
Fri Oct 04, 2019 7:07 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Search speed
Replies: 9
Views: 1119

Re: Search speed

I guess it was Kenny Rogers who said it best, "... knowing what to throw away and knowing what to keep ..."
That is the gist of search, as I see it.

If you want to find the vein of gold in the mountain, you follow the flakes in the stream.
by Dann Corbit
Fri Oct 04, 2019 4:36 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Search speed
Replies: 9
Views: 1119

Re: Search speed

Use of the CPU cache is automatic. The hardware itself handles that. It would be a mistake, though, to limit hash size to the hardware cache. The most important thing for search speed is not nps but branching factor. If you want the fastest search, the best place to spend effort is branching factor....
by Dann Corbit
Fri Oct 04, 2019 4:23 pm
Forum: Computer Chess Club: General Topics
Topic: buying a new computer
Replies: 280
Views: 32357

Re: buying a new computer

If 4 cards don't work together, even with 8 channel memory and PCie4, you could always run 2 pairs of 2 cards with two instances of LC0 to double your throughput. I do admit it is a gamble to go after any software implementation + hardware combination that has never been tried. People reported here...
by Dann Corbit
Fri Oct 04, 2019 3:04 am
Forum: Computer Chess Club: General Topics
Topic: Stockfish mates Allie in 34 moves / TCEC
Replies: 20
Views: 2364

Re: Stockfish mates Allie in 34 moves / TCEC

Maybe it was a strange SMP thing, but I get b4: r2q1rk1/pb2bpp1/3p1n1p/1ppP2N1/4PP1P/P5P1/1PQB2B1/R3K2R b KQ - acd 42; acs 180; bm b4; ce -31; pm b4; pv b4 axb4 cxb4 e5 dxe5 fxe5 Re8 Kd1 Qd7 Qd3 Bf8 exf6 hxg5 hxg5 g6 Rh4 Rac8 Be4 Rxe4 Rxe4 Bxd5 Ra5 Bc5 Rc4 Rd8 Kc2 b3+ Kc3 Bxc4 Qxd7 Rxd7 Rxc5 Be6 Rb5...
by Dann Corbit
Fri Oct 04, 2019 2:58 am
Forum: Computer Chess Club: General Topics
Topic: buying a new computer
Replies: 280
Views: 32357

Re: buying a new computer

If 4 cards don't work together, even with 8 channel memory and PCie4, you could always run 2 pairs of 2 cards with two instances of LC0 to double your throughput.

I do admit it is a gamble to go after any software implementation + hardware combination that has never been tried.