2D Power Consumption on 3D Graphics Cards

[Tony.McK]

Hullooo, Folks!

A wee query regarding graphics cards:

Anyone know if the big power-hungry NVIDIA / ATI beasties scale back
their power consumption when outputting in 2D mode? Or do they just
carry on watt-gobbling regardless?

For eg: Many hardware review sites have graphs that show system
wattage consumption in these card's 3D 'idle' and 'load' states; say,
for a powerful gaming card like the 'GeForce GTX 280' they may show
wattage as 160 watts (idle) and 330 watts (full load) when running a
top-notch game - but reviewers never seem to state the power draw of
such cards when, say, you are using the computer for a more mundane
'2D task' - writing a letter in MS Word for instance. (Unless the idle
state **is** the '2D' state - in which case I've just made a right
public plonker of myself...) Also, the graphs do state 'system power
consumption' - but these big cards do account for the lion's share of
that consumption when gaming or outputting HD movies, etc.

Yes, I know what you're thinking: 'Tony, ya don't buy a friggin' GTX
280 to load up 'Word' on the screen!"

But, when the gaming is done, what about those every-day chores we all
have to do with our PCs... y'know, the grocery lists, letters, e-
mails, payin' bills, porn - ohmygoddidisaythat-
where'sthedeletekey! ;-)

Do these monster cards 'sense' the lighter visual requirement and
dramatically scale back their wattage apetites?

This scenario will become increasingly important as computers and
their graphics cards become more powerful, our tastes for digital
visual candy on our PCs grow, and as household electricity costs climb
relentlessly up the wattage ladder. Bet'cha it'll be the next 'big
thing' feature-wise.

The boffins are rising to meet the challenge: There are cards like the
new 'Asus EN9600GT MATRIX' which has 'built-in intelligence' that
senses the visual task at hand and scales wattage up or down to suite;
and a similar 'hybrid power' capability with some NVIDIA cards in
conjunction with GeForce mobos. That said, I've always thought that
the big NVIDIA / ATI cards scaled their power consumption to suite the
task anyway, but lately I've had my doubts about that assumption -
hence, this post.

Any advice appreciated.


Cheers, Tony McKee

 

[Ed Medlin]

Hullooo, Folks!

A wee query regarding graphics cards:

Anyone know if the big power-hungry NVIDIA / ATI beasties scale back
their power consumption when outputting in 2D mode? Or do they just
carry on watt-gobbling regardless?

For eg: Many hardware review sites have graphs that show system
wattage consumption in these card's 3D 'idle' and 'load' states; say,
for a powerful gaming card like the 'GeForce GTX 280' they may show
wattage as 160 watts (idle) and 330 watts (full load) when running a
top-notch game - but reviewers never seem to state the power draw of
such cards when, say, you are using the computer for a more mundane
'2D task' - writing a letter in MS Word for instance. (Unless the idle
state **is** the '2D' state - in which case I've just made a right
public plonker of myself...) Also, the graphs do state 'system power
consumption' - but these big cards do account for the lion's share of
that consumption when gaming or outputting HD movies, etc.

Yep.............idle IS the 2D state......... Playing a DVD doesn't kick
my 2 GTXs (SLI) into 3D mode either. They pretty much stay in 2D mode for
everything except gaming. Mine (EVGA Superclocked) are very quiet and the
only way to know they are kicking into 3D mode is a very low 'hissing' sound
when the fans start to go into high gear.


Ed

 

[Tony.McK]

Yep.............idle IS the 2D state.........

Well... what can I say...? SPLASH!!! I'll be lucky if I'm ever taken
seriously in these groups again! ;-) Thanks for putting my assumption
back in the right dimension.

Playing a DVD doesn't kick
my 2 GTXs (SLI) into 3D mode either. They pretty much stay in 2D mode for
everything except gaming. Mine (EVGA Superclocked) are very quiet and the
only way to know they are kicking into 3D mode is a very low 'hissing' sound
when the fans start to go into high gear.

Sounds nice. Rather like the new GTX 280s - damned if I can decide
between one of them or a Radeon 4570 for a new rig. Nvidea's CUDA
thing really appeals - and this growing idea of utilising their card's
GPUs for tasks like fast HD video encoding. If these devices are going
to sit there eating watts anyway, they may as well be put to some
useful work. Watch that space.

Cheers, Tony McKee

 

[Paul]

Well... what can I say...? SPLASH!!! I'll be lucky if I'm ever taken
seriously in these groups again! ;-) Thanks for putting my assumption
back in the right dimension.


Sounds nice. Rather like the new GTX 280s - damned if I can decide
between one of them or a Radeon 4570 for a new rig. Nvidea's CUDA
thing really appeals - and this growing idea of utilising their card's
GPUs for tasks like fast HD video encoding. If these devices are going
to sit there eating watts anyway, they may as well be put to some
useful work. Watch that space.

Cheers, Tony McKee

Xbitlabs.com does measurements for video cards, using a few specially
modified motherboards. They can measure the slot power and the Aux
connector power, under various test conditions. These are power measurements
at the actual card level, and not just a total system power measured at
the AC power connector of the computer.

http://www.xbitlabs.com/articles/video/display/geforce-gtx200-theory_12.html

The detail picture here, shows examples of three test conditions.
Idle is a 2D condition.

Idle, Peak 2D, Peak3D

GTX280 = 50.2W, 78.9W, 178.0W
GTX260 = 44.8W, 65.4W, 136.1W

http://www.xbitlabs.com/images/video/geforce-gtx200-theory/gtx200_power_full.png

Some comparative numbers for the HD 4860 and HD 4870 can be seen here.

http://www.xbitlabs.com/articles/video/display/geforce9800gtx-voltmodding_3.html

HD4870 = 65.2W, 80.4W, 130.0W
HD4850 = 40.7W, 61.2W, 109.9W

The 4870X2 (dual GPU) power is here. The power trend is interesting when
compared to the single GPU case.

http://www.xbitlabs.com/articles/video/display/radeon-hd4870-x2_6.html

HD4870X2 = 78.9W, 86.5W, 263.9W

HTH,
Paul

 

[Tony.McK]

Xbitlabs.com does measurements for video cards, using a few specially
modified motherboards. They can measure the slot power and the Aux
connector power, under various test conditions. These are power measurements
at the actual card level, and not just a total system power measured at
the AC power connector of the computer.

Thanks! That Xbitlabs review was just the thing I was after. You're a
champion!


Cheers, Tony McKee

 

[Tony.McK]

yep, new options are coming out to use onboard video for 2d and kickin
the seperate 3d card for games...however, the cheaper boards are the
ones with on-board gpu....ie cheap capacitors, limited stages of voltage
regulation etc etc so Im not that convinced it is going to be a biggee...

Given base laptops are pushing under $700 it may make sense to have 2
machines...laptop for 2d and dedicated machine for 3d...

Hmmmmm..... now there's an idea.

That said, I've always thought that


They scale back, but not that well. If you are building a "decent"
gaming rig then bad power consumption in 2D is something you live with
IMHO...ie there are other hi-performance bits like lots of ram and big
PSUs that are essential that also dont scale back well.



Whats the Q?

(Sheepish look) Not sure now. I'm just trying to tick those 'factor
boxes' that have to be considered before parting out a fair swag of
dosh on parts for a new rig - VGA card power draws being but one of
those factors. Probably my original post was merely a subconscious
plea for reassurance from greater technical minds than mine! Thank God
for computer newsgroups... ;-)

Cheers, Tony McKee