Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Two questions

Author: Robert Hyatt

Date: 06:19:55 05/17/99

Go up one level in this thread


On May 17, 1999 at 04:18:23, Paulo Soares wrote:

>1. What is a null move?

It is a tree-pruning algorithm based loosely on the concept that if you
could make two consecutive moves without the opponent getting to make a
move, you would easily win such a position (ie move 1 you attack your
opponent's queen, move 2 you take it, or move one you threaten mate and
move 2 you mate.

The idea is that since this is _so_ powerful an advantage, if you can do
such a "null-move" (ie you simply 'pass' and don't move, and your opponent
_still_ can't do something deadly to you, then this position (ours) is so
good we can avoid searching further.

I can explain more if you want, but you seemed to be asking conceptually
rather than for an implementation...


>2. Somebody could make a summary of what is DB Junior?
>   Nodes p/sec, estimated rating, etc.


it is based on one IBM SP processor, with 16 DB chess chips.  It searches
about 16-32M nodes per second and produced a performance rating of well over
2700 over dozens of GM games during the development of DB.  Hsu is reportedly
(IEEE Micro, current issue) going to re-fab the DB chip to produce a single
chip that will search roughly 36M nodes per second, and then sell it as a PC
card that anyone can add to their PC.

that's all that is known at present.





>
>Thanks in advance,
>Paulo Soares, from Brazil



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.