<s>
The	O
thermal	B-General_Concept
design	I-General_Concept
power	I-General_Concept
(	O
TDP	O
)	O
,	O
sometimes	O
called	O
thermal	B-General_Concept
design	I-General_Concept
point	I-General_Concept
,	O
is	O
the	O
maximum	O
amount	O
of	O
heat	O
generated	O
by	O
a	O
computer	O
chip	O
or	O
component	O
(	O
often	O
a	O
CPU	B-Device
,	O
GPU	B-Architecture
or	O
system	B-Architecture
on	I-Architecture
a	I-Architecture
chip	I-Architecture
)	O
that	O
the	O
cooling	B-General_Concept
system	I-General_Concept
in	O
a	O
computer	O
is	O
designed	O
to	O
dissipate	O
under	O
any	O
workload	O
.	O
</s>
<s>
Intel	O
has	O
introduced	O
a	O
new	O
metric	O
called	O
scenario	O
design	O
power	O
(	O
SDP	O
)	O
for	O
some	O
Ivy	B-Device
Bridge	I-Device
Y-series	O
processors	O
.	O
</s>
<s>
The	O
average	B-General_Concept
CPU	I-General_Concept
power	I-General_Concept
(	O
ACP	O
)	O
is	O
the	O
power	O
consumption	O
of	O
central	B-General_Concept
processing	I-General_Concept
units	I-General_Concept
,	O
especially	O
server	B-Application
processors	O
,	O
under	O
"	O
average	O
"	O
daily	O
usage	O
as	O
defined	O
by	O
Advanced	O
Micro	O
Devices	O
(	O
AMD	O
)	O
for	O
use	O
in	O
its	O
line	O
of	O
processors	O
based	O
on	O
the	O
K10	O
microarchitecture	O
(	O
Opteron	B-General_Concept
8300	O
and	O
2300	O
series	O
processors	O
)	O
.	O
</s>
<s>
Intel	O
's	O
thermal	B-General_Concept
design	I-General_Concept
power	I-General_Concept
(	O
TDP	O
)	O
,	O
used	O
for	O
Pentium	O
and	O
Core	O
2	O
processors	O
,	O
measures	O
the	O
energy	O
consumption	O
under	O
high	O
workload	O
;	O
it	O
is	O
numerically	O
somewhat	O
higher	O
than	O
the	O
"	O
average	O
"	O
ACP	O
rating	O
of	O
the	O
same	O
processor	O
.	O
</s>
<s>
which	O
AMD	O
said	O
is	O
an	O
appropriate	O
method	O
of	O
power	O
consumption	O
measurement	O
for	O
data	B-Operating_System
centers	I-Operating_System
and	O
server-intensive	O
workload	O
environments	O
.	O
</s>
<s>
Barcelona	O
and	O
later	O
server	B-Application
processors	O
have	O
the	O
two	O
power	O
figures	O
.	O
</s>
<s>
The	O
TDP	O
of	O
a	O
CPU	B-Device
has	O
been	O
underestimated	O
in	O
some	O
cases	O
,	O
leading	O
to	O
certain	O
real	O
applications	O
(	O
typically	O
strenuous	O
,	O
such	O
as	O
video	O
encoding	O
or	O
games	O
)	O
causing	O
the	O
CPU	B-Device
to	O
exceed	O
its	O
specified	O
TDP	O
and	O
resulting	O
in	O
overloading	O
the	O
computer	O
's	O
cooling	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
In	O
this	O
case	O
,	O
CPUs	B-Device
either	O
cause	O
a	O
system	O
failure	O
(	O
a	O
"	O
therm-trip	O
"	O
)	O
or	O
throttle	O
their	O
speed	O
down	O
.	O
</s>
<s>
Most	O
modern	O
processors	O
will	O
cause	O
a	O
therm-trip	O
only	O
upon	O
a	O
catastrophic	O
cooling	O
failure	O
,	O
such	O
as	O
a	O
no	O
longer	O
operational	O
fan	B-Application
or	O
an	O
incorrectly	O
mounted	O
heat	O
sink	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
laptop	B-Device
's	O
CPU	B-General_Concept
cooling	I-General_Concept
system	O
may	O
be	O
designed	O
for	O
a	O
20W	O
TDP	O
,	O
which	O
means	O
that	O
it	O
can	O
dissipate	O
up	O
to	O
20watts	O
of	O
heat	O
without	O
exceeding	O
the	O
maximum	O
junction	O
temperature	O
for	O
the	O
laptop	B-Device
's	O
CPU	B-Device
.	O
</s>
<s>
A	O
cooling	B-General_Concept
system	I-General_Concept
can	O
do	O
this	O
using	O
an	O
active	O
cooling	O
method	O
(	O
e.g.	O
</s>
<s>
conduction	O
coupled	O
with	O
forced	O
convection	O
)	O
such	O
as	O
a	O
heat	O
sink	O
with	O
a	O
fan	B-Application
,	O
or	O
any	O
of	O
the	O
two	O
passive	O
cooling	O
methods	O
:	O
thermal	O
radiation	O
or	O
conduction	O
.	O
</s>
<s>
Since	O
safety	O
margins	O
and	O
the	O
definition	O
of	O
what	O
constitutes	O
a	O
real	O
application	O
vary	O
among	O
manufacturers	B-Algorithm
,	O
TDP	O
values	O
between	O
different	O
manufacturers	B-Algorithm
cannot	O
be	O
accurately	O
compared	O
(	O
a	O
processor	O
with	O
a	O
TDP	O
of	O
,	O
for	O
example	O
,	O
100W	O
will	O
almost	O
certainly	O
use	O
more	O
power	O
at	O
full	O
load	O
than	O
processors	O
with	O
a	O
fraction	O
of	O
said	O
TDP	O
,	O
and	O
very	O
probably	O
more	O
than	O
processors	O
with	O
lower	O
TDP	O
from	O
the	O
same	O
manufacturer	O
,	O
but	O
it	O
may	O
or	O
may	O
not	O
use	O
more	O
power	O
than	O
a	O
processor	O
from	O
a	O
different	O
manufacturer	O
with	O
a	O
not	O
excessively	O
lower	O
TDP	O
,	O
such	O
as	O
90W	O
)	O
.	O
</s>
<s>
Intel	O
calculates	O
a	O
specified	O
chip	O
's	O
TDP	O
according	O
to	O
the	O
amount	O
of	O
power	O
the	O
computer	O
's	O
fan	B-Application
and	O
heatsink	O
need	O
to	O
be	O
able	O
to	O
dissipate	O
while	O
the	O
chip	O
is	O
under	O
sustained	O
load	O
.	O
</s>
<s>
In	O
particular	O
,	O
Intel	O
's	O
measurement	O
also	O
does	O
not	O
fully	O
take	O
into	O
account	O
Intel	B-Device
Turbo	I-Device
Boost	I-Device
due	O
to	O
the	O
default	O
time	O
limits	O
,	O
while	O
AMD	O
does	O
because	O
AMD	B-Device
Turbo	I-Device
Core	I-Device
always	O
tries	O
to	O
push	O
for	O
the	O
maximum	O
power	O
.	O
</s>
<s>
As	O
another	O
example	O
,	O
some	O
of	O
the	O
AMD	B-General_Concept
Opteron	I-General_Concept
processors	O
and	O
Kaveri	O
APUs	B-Architecture
can	O
be	O
configured	O
for	O
lower	O
TDP	O
values	O
.	O
</s>
<s>
IBM	O
's	O
POWER8	B-Device
processor	O
implements	O
a	O
similar	O
power	O
capping	O
functionality	O
through	O
its	O
embedded	O
on-chip	O
controller	O
(	O
OCC	O
)	O
.	O
</s>
