<s>
Hydra	B-Architecture
was	O
a	O
chess	B-Application
machine	O
,	O
designed	O
by	O
a	O
team	O
with	O
Dr.	O
Christian	O
"	O
Chrilly	O
"	O
Donninger	O
,	O
Dr.	O
Ulf	O
Lorenz	O
,	O
GM	O
Christopher	O
Lutz	O
and	O
Muhammad	O
Nasir	O
Ali	O
.	O
</s>
<s>
Hydra	B-Architecture
was	O
under	O
the	O
patronage	O
of	O
the	O
PAL	O
Group	O
and	O
Sheikh	O
Tahnoon	O
Bin	O
Zayed	O
Al	O
Nahyan	O
of	O
Abu	O
Dhabi	O
.	O
</s>
<s>
The	O
goal	O
of	O
the	O
Hydra	B-Architecture
Project	O
was	O
to	O
dominate	O
the	O
computer	B-Application
chess	I-Application
world	O
,	O
and	O
finally	O
have	O
an	O
accepted	O
victory	O
over	O
humans	O
.	O
</s>
<s>
Hydra	B-Architecture
represented	O
a	O
potentially	O
significant	O
leap	O
in	O
the	O
strength	O
of	O
computer	B-Application
chess	I-Application
.	O
</s>
<s>
Design	O
team	O
member	O
Lorenz	O
estimates	O
its	O
FIDE	O
equivalent	O
playing	O
strength	O
to	O
be	O
over	O
Elo	O
3000	O
,	O
and	O
this	O
is	O
in	O
line	O
with	O
its	O
results	O
against	O
Michael	O
Adams	O
and	O
Shredder	B-Application
8	O
,	O
the	O
former	O
micro-computer	O
chess	O
champion	O
.	O
</s>
<s>
Hydra	B-Architecture
began	O
competing	O
in	O
2002	O
and	O
played	O
its	O
last	O
game	O
in	O
June	O
2006	O
.	O
</s>
<s>
In	O
June	O
2009	O
,	O
Christopher	O
Lutz	O
stated	O
that	O
"	O
unfortunately	O
the	O
Hydra	B-Architecture
project	O
is	O
discontinued.	O
"	O
</s>
<s>
The	O
Hydra	B-Architecture
team	O
originally	O
planned	O
to	O
have	O
Hydra	B-Architecture
appear	O
in	O
four	O
versions	O
:	O
Orthus	O
,	O
Chimera	O
,	O
Scylla	B-Language
and	O
then	O
the	O
final	O
Hydra	B-Architecture
version	O
–	O
the	O
strongest	O
of	O
them	O
all	O
.	O
</s>
<s>
The	O
original	O
version	O
of	O
Hydra	B-Architecture
evolved	O
from	O
an	O
earlier	O
design	O
called	O
Brutus	O
and	O
works	O
in	O
a	O
similar	O
fashion	O
to	O
Deep	B-General_Concept
Blue	I-General_Concept
,	O
utilising	O
large	O
numbers	O
of	O
purpose-designed	O
chips	O
(	O
in	O
this	O
case	O
implemented	O
as	O
a	O
field-programmable	B-Architecture
gate	I-Architecture
array	I-Architecture
or	O
FPGA	B-Architecture
)	O
.	O
</s>
<s>
In	O
Hydra	B-Architecture
,	O
there	O
are	O
multiple	O
computers	O
,	O
each	O
with	O
its	O
own	O
FPGA	B-Architecture
acting	O
as	O
a	O
chess	B-Application
coprocessor	O
.	O
</s>
<s>
These	O
co-processors	O
enabled	O
Hydra	B-Architecture
to	O
search	O
enormous	O
numbers	O
of	O
positions	O
per	O
second	O
,	O
making	O
each	O
processor	O
more	O
than	O
ten	O
times	O
faster	O
than	O
an	O
unaided	O
computer	O
.	O
</s>
<s>
Hydra	B-Architecture
ran	O
on	O
a	O
32-node	O
Intel	B-Device
Xeon	I-Device
with	O
a	O
Xilinx	O
FPGA	B-Architecture
accelerator	O
card	O
cluster	B-Architecture
,	O
with	O
a	O
total	O
of	O
64	O
gigabytes	O
of	O
RAM	B-Architecture
.	O
</s>
<s>
It	O
evaluates	O
about	O
150,000,000	O
chess	B-Application
positions	O
per	O
second	O
,	O
roughly	O
the	O
same	O
as	O
the	O
1997	O
Deep	B-General_Concept
Blue	I-General_Concept
which	O
defeated	O
Garry	O
Kasparov	O
,	O
but	O
with	O
several	O
times	O
more	O
overall	O
computing	O
power	O
.	O
</s>
<s>
Whilst	O
FPGAs	B-Architecture
generally	O
have	O
a	O
lower	O
performance	O
level	O
than	O
ASIC	O
chips	O
,	O
modern-day	O
FPGAs	B-Architecture
run	O
about	O
as	O
fast	O
as	O
the	O
older	O
ASICs	O
used	O
for	O
Deep	B-General_Concept
Blue	I-General_Concept
.	O
</s>
<s>
The	O
engine	O
is	O
on	O
average	O
able	O
to	O
evaluate	O
up	O
to	O
a	O
depth	O
of	O
about	O
18	O
ply	O
(	O
nine	O
moves	O
by	O
each	O
player	O
)	O
,	O
whereas	O
Deep	B-General_Concept
Blue	I-General_Concept
only	O
evaluated	O
to	O
about	O
12	O
ply	O
on	O
average	O
.	O
</s>
<s>
Hydra	B-Architecture
's	O
search	O
used	O
alpha-beta	B-Algorithm
pruning	I-Algorithm
as	O
well	O
as	O
null-move	B-Algorithm
heuristics	I-Algorithm
.	O
</s>
<s>
The	O
Hydra	B-Architecture
computer	O
was	O
physically	O
located	O
in	O
Abu	O
Dhabi	O
,	O
in	O
the	O
United	O
Arab	O
Emirates	O
,	O
and	O
was	O
usually	O
operated	O
over	O
a	O
high	O
speed	O
optical	O
fiber	O
based	O
network	O
link	O
.	O
</s>
<s>
In	O
July	O
2002	O
,	O
Brutus	O
finished	O
third	O
in	O
the	O
World	O
Computer	B-Application
Chess	I-Application
Championship	O
in	O
Maastricht	O
,	O
the	O
Netherlands	O
.	O
</s>
<s>
The	O
loss	O
,	O
against	O
Deep	B-Application
Junior	I-Application
,	O
included	O
a	O
rook	O
sacrifice	O
for	O
very	O
long	O
term	O
compensation	O
,	O
which	O
the	O
additional	O
computing	O
power	O
of	O
Brutus	O
could	O
not	O
help	O
it	O
to	O
understand	O
.	O
</s>
<s>
In	O
November	O
2003	O
,	O
Brutus	O
finished	O
fourth	O
in	O
the	O
World	O
Computer	B-Application
Chess	I-Application
Championship	O
in	O
Graz	O
,	O
Austria	O
.	O
</s>
<s>
In	O
February	O
2004	O
,	O
Hydra	B-Architecture
won	O
the	O
13th	O
IPCCC	O
(	O
International	O
Paderborn	O
Computer	B-Application
Chess	I-Application
Championship	O
)	O
tournament	O
.	O
</s>
<s>
Hydra	B-Architecture
scored	O
6½	O
out	O
of	O
7	O
,	O
ahead	O
of	O
Fritz	O
and	O
Shredder	B-Application
.	O
</s>
<s>
In	O
April	O
2004	O
,	O
Hydra	B-Architecture
finished	O
second	O
in	O
the	O
International	O
CSVN	O
Tournament	O
in	O
Leiden	O
,	O
the	O
Netherlands	O
.	O
</s>
<s>
It	O
won	O
five	O
games	O
,	O
lost	O
one	O
game	O
,	O
and	O
drew	O
three	O
,	O
leaving	O
it	O
with	O
6½	O
points	O
out	O
of	O
9	O
,	O
1½	O
points	O
behind	O
winner	O
Shredder	B-Application
.	O
</s>
<s>
In	O
August	O
2004	O
,	O
at	O
the	O
14th	O
Abu	O
Dhabi	O
International	O
Chess	B-Application
Festival	O
,	O
Hydra	B-Architecture
played	O
an	O
eight-game	O
match	O
against	O
the	O
computer	O
program	O
Shredder	B-Application
8	O
,	O
a	O
multiple-time	O
world	O
computer	B-Application
chess	I-Application
champion	O
.	O
</s>
<s>
Running	O
on	O
"	O
just	O
"	O
16	O
nodes	O
Hydra	B-Architecture
defeated	O
Shredder	B-Application
5½	O
to	O
2½	O
,	O
winning	O
three	O
games	O
and	O
drawing	O
the	O
rest	O
.	O
</s>
<s>
In	O
an	O
informal	O
match	O
at	O
the	O
same	O
tournament	O
,	O
Hydra	B-Architecture
took	O
on	O
International	O
Grandmaster	O
Evgeny	O
Vladimirov	O
of	O
Kazakhstan	O
,	O
and	O
defeated	O
him	O
by	O
a	O
score	O
of	O
3½	O
to	O
½	O
.	O
</s>
<s>
In	O
October	O
2004	O
,	O
in	O
a	O
man	O
vs.	O
machine	O
contest	O
,	O
Hydra	B-Architecture
defeated	O
former	O
FIDE	O
world	O
champion	O
Ruslan	O
Ponomariov	O
in	O
both	O
of	O
their	O
games	O
.	O
</s>
<s>
In	O
February	O
2005	O
,	O
Hydra	B-Architecture
won	O
the	O
14th	O
IPCCC	O
(	O
International	O
Paderborn	O
Computer	B-Application
Chess	I-Application
Championships	O
)	O
tournament	O
.	O
</s>
<s>
Hydra	B-Architecture
scored	O
8	O
points	O
out	O
of	O
9	O
(	O
seven	O
wins	O
and	O
two	O
draws	O
)	O
,	O
defeating	O
chess	B-Application
program	O
Shredder	B-Application
again	O
in	O
the	O
process	O
.	O
</s>
<s>
Due	O
to	O
human	O
handler	O
errors	O
and	O
program	O
errors	O
,	O
Hydra	B-Architecture
did	O
not	O
fare	O
well	O
in	O
the	O
June	O
2005	O
PAL/CSS	O
Freestyle	O
Chess	B-Application
Tournament	O
,	O
an	O
online	O
tournament	O
where	O
players	O
are	O
allowed	O
to	O
access	O
any	O
and	O
all	O
resources	O
to	O
them	O
,	O
including	O
computer	O
engines	O
,	O
databases	O
,	O
as	O
well	O
as	O
human	O
grandmasters	O
.	O
</s>
<s>
Two	O
versions	O
of	O
Hydra	B-Architecture
participated	O
in	O
the	O
tournament	O
-	O
Hydra	B-Architecture
Chimera	O
(	O
without	O
human	O
intervention	O
)	O
scored	O
3½/8	O
,	O
and	O
Hydra	B-Architecture
Scylla	B-Language
(	O
with	O
human	O
intervention	O
)	O
scored	O
4/8	O
.	O
</s>
<s>
Neither	O
version	O
of	O
Hydra	B-Architecture
qualified	O
for	O
the	O
quarter-finals	O
.	O
</s>
<s>
From	O
June	O
21	O
to	O
June	O
27	O
,	O
2005	O
,	O
Hydra	B-Architecture
played	O
a	O
six-game	O
match	O
against	O
Michael	O
Adams	O
,	O
the	O
top	O
British	O
player	O
and	O
ranked	O
seventh	O
in	O
the	O
world	O
.	O
</s>
<s>
Hydra	B-Architecture
defeated	O
Adams	O
by	O
a	O
score	O
of	O
5½	O
to	O
½	O
;	O
Adams	O
lost	O
each	O
game	O
except	O
for	O
game	O
2	O
which	O
he	O
drew	O
.	O
</s>
<s>
This	O
version	O
of	O
Hydra	B-Architecture
was	O
running	O
on	O
half	O
power	O
;	O
only	O
32	O
out	O
of	O
64	O
nodes	O
were	O
utilized	O
.	O
</s>
<s>
Adams	O
played	O
against	O
the	O
Scylla	B-Language
version	O
of	O
Hydra	B-Architecture
.	O
</s>
<s>
In	O
November	O
2005	O
,	O
Hydra	B-Architecture
played	O
4	O
games	O
:	O
it	O
beat	O
Rustam	O
Kasimdzhanov	O
,	O
drew	O
with	O
Alexander	O
Khalifman	O
,	O
beat	O
Ruslan	O
Ponomariov	O
and	O
finally	O
drew	O
with	O
Rustam	O
Kasimdzhanov	O
.	O
</s>
<s>
In	O
the	O
April	O
2006	O
PAL/CSS	O
Freestyle	O
Chess	B-Application
Tournament	O
Hydra	B-Architecture
finished	O
first	O
with	O
a	O
score	O
of	O
5½/7	O
,	O
a	O
full	O
point	O
ahead	O
of	O
the	O
field	O
.	O
</s>
<s>
All	O
64	O
of	O
Hydra	B-Architecture
's	O
nodes	O
were	O
utilized	O
.	O
</s>
<s>
In	O
the	O
June	O
2006	O
PAL/CSS	O
Freestyle	O
Chess	B-Application
Main	O
Tournament	O
Hydra	B-Architecture
finished	O
tied	O
for	O
fifth-sixteenth	O
.	O
</s>
<s>
Hydra	B-Architecture
was	O
not	O
defeated	O
by	O
an	O
unaided	O
human	O
player	O
in	O
over-the-board	O
play	O
.	O
</s>
<s>
Hydra	B-Architecture
has	O
,	O
however	O
,	O
been	O
beaten	O
by	O
humans	O
who	O
had	O
access	O
to	O
other	O
programs	O
during	O
their	O
games	O
;	O
for	O
example	O
,	O
correspondence	O
chess	B-Application
International	O
Grandmaster	O
Arno	O
Nickel	O
beat	O
an	O
older	O
version	O
of	O
Hydra	B-Architecture
in	O
a	O
two-game	O
correspondence	O
match	O
lasting	O
six	O
months	O
.	O
</s>
