DXVA power consuption

[daWsOn_s]

having an ATI HD2xxx series and Intel core2duo e6750, what will consumes more power for decoding a h.264 1080p video?

I know that GPU consumes a lot more than CPU so is it really worth it to use DVXA hardware acceleration in terms of power saving?

[Dark Shikari]

DXVA doesn't use the GPU, it uses a dedicated ASIC on the graphics card for decoding. The power usage is likely near-zero.

[daWsOn_s]

Great didn't know that.:)

thanks

So the video decoding performance has nothing to do with clock frequency of the GPU?

[Blue_MiSfit]

Nope. If a card has the requisite DXVA capabilities, it will decode in real-time regardless of the clock frequency.

I wonder what would happen if you underclocked the card severely :devil:

~MiSfit

[mariush]

I did some readings a while ago ... q6600, 4gb memory, 3 hard drives, 4850 ... 166w idle, about 170-172 when decoding with dxva, about 175-177 when using cpu (ffmpeg) so I could say almost within error margin. It think it was 720p content but I doubt it would be a bigger difference with 1080p

[dvy]

If DXVA use shader decode,then DXVA consumes large power,if DXVA use "dedicated video decoding unit" ,then DXVA consumes a little power.both of Nvidia and ATI use "dedicated video decoding unit" for DXVA ,Nvidia is PureVideo HD,ATI is UVD,so DXVA consumes lesser than CPU decoding power.

[daWsOn_s]

Very helpful everyone :thanks:

[deekey777]

ATI HD2xxx series?

I hope, it's not a HD2900XT...
Here are some numbers during watching a Blu-ray (graphics cards only!): http://ht4u.net/reviews/2009/sapphire_radeon_hd5750_vaporx/index13.php




Here are some number for low/mid-end graphics cards: http://ht4u.net/reviews/2009/einsteiger_grafik_roundup/index28.php