GFX cards,how high do i need?

custardy

okay,Im years out of date on GFX cards
last couple of PCs have been bought off the shelf
last card i bought was a Radeon x1650 pro :eek::o

So i have a PC here
core2quad 8400
4gb DDR3
motherboard with Intel X4500 graphics

machine is used for net,office work,burning,downloading etc
I dont really game on the PC except for the likes of RTS games

however,what i do need the machine is as a media hub to run dual screen with the likes of XBMC
so it will drive a 22" monitor over DVI and a 50" plasma 1080p TV over HDMI
plus transcoding duties over wifi/gigabit to PS3/360 on other TV's

so what do i need to run smooth HD video?
the Intel X4500 plays HD over HDMI,but its not smooth but still watchable to a point.
neither the CPU or ram are being taxed at all.

looking to go no higher than £100ish
so had looked at the likes of a 2nd hand Radeon HD 5850?

or would a 5670 level card be enough?

http://www.cclonline.com/product-info.asp?product_id=66298&category_id=1134&manufacturer_id=0&tid=hd-567x-zaf3

or other suggestions?

cheers

Hammyman

Any card you want. Even a £20 nVidia 9600GT off Ebay is more than up to it. Transcoding is done by the CPU, not the graphics card.

A.Penny.Saved

Hammyman wrote: »

....Transcoding is done by the CPU, not the graphics card.

Graphics cards by nVidia (GPU's) can assist with transcoding. At the least they can assist decoding of H.264/VC-1 and other formats which saves CPU cycles for re-encoding purposes and therefore speeds it up. GPU's can also re-encode video themselves but only if speed is more important than quality. Checkout Badaboom.


It doesn't sound like you need a high end card.

Transcoding can be assisted by a graphics card as it can decode Mpeg 4 AVC (H.264) or VC-1 Hi Def video which means the CPU time doesn't get used up decoding the video. Instead the CPU time can be put to re-encoding the video. There are few programs that can do this ATM. MediaCoder can and so can DGDecodeNV AVISynth plugin. Both of these use CUDA as part of nVidia graphics cards. MediaCoder uses OpenCandy adware.

GPU encoding can also be done but the quality is fairly poor in comparison to x264.

http://www.mediacoderhq.com/cuda/index.html

nVidia cards do have the CUDA advantage and they have done a lot to push CUDA development. There are quite a few commercial applications which use CUDA such as Badaboom, CoreAVC, PowerDVD etc. ATI/AMD graphics cards are meant to work better when outputting HD audio over HDMI. I have had both ATI and nVidia cards over the last 2/3 years but I have not tried HDMI audio so cannot comment on whether ATI is better than nVidia in this respect.

custardy

Hammyman wrote: »

Any card you want. Even a £20 nVidia 9600GT off Ebay is more than up to it. Transcoding is done by the CPU, not the graphics card.

but the GFX card is used for straight playback of media over HDMI?

A.Penny.Saved

custardy wrote: »

but the GFX card is used for straight playback of media over HDMI?

Yes, just like DVI or VGA as it is just another connection on newer graphics cards. But newer cards have better support for audio over HDMI like I said, whereas older cards are poor so are probably better avoided.

DVI connectors can be converted to HDMI but audio is a problem as DVI has no audio.

Decoding assistance of H.264/VC-1 Hi Def video is performed by a part of the Graphics core called a video processing (VP) engine on nVidia GPU's/cards. That comes in different versions with the most recent VP4 being the most capable and can help decode Mpeg4 ASP video such as XVid as well as having bugs corrected in the original implementation. nVidia refer to it as Purevideo decoding.

The VP4 is present on GT 210/220/240 and newer cards.

CUDA is a programming framework to use the nVidia hardware and it can work with Purevideo or more advanced GPU encoding.

For GPU encoding the number of CUDA cores is important as the more there are the faster the work is done. Higher end GPU's have more than lower end ones.

http://en.wikipedia.org/wiki/Nvidia_PureVideo

So depending upon what you want to do will dictate whether something like CUDA cores or Purevideo is important if you purchase an nVidia GPU.

ATI/AMD are very good but they do little to encourage development for their GPU's unfortunately. I purchased an ATI HD3850 but found that only an nVidia card would allow GPU assistance when transcoding so I purchased a GT 240 1GB which can decode HD video at about 100fps which is far faster than it can be re-encoded by the CPU.

If you use a PS3 then I doubt whether any of this is important as I don't think any of the PS3 transcoders currently in existence can use a GPU for assistance. But it should be possible.

custardy

yeah I would want a unit with HDMI built in
means i can feed it direct to the surround amp
so it seems Nvidia has the edge on the video side of things in the GPU stakes?
the PS3/360 transcoding is less important
its only (now) used for the odd bit of streaming to the Tv's upstairs in the bedrooms
the main 50" plasma is in the living room and fed by HDMI
this is where i want the machine to be able to take anything i throw at it
I'll probably add Bluray to the PC as well and totally remove the PS3 from the downstairs equation

A.Penny.Saved

nVidia has the edge with CUDA but I would say that is the only benefit. ATI/AMD cards were the first to have audio over HDMI, nVidia has been improving that and the more recent gen cards should have it sorted. I don't know how well it works on nvidia I don't know not having used it as I don't have HDMI available on my TV. nVidia does have 4 HD audio devices in device manager on my system but it looks like it works differently to ATI. With ATI the default sound output device needs to be set to the ATI HD audio device and that means all sound goes to that rather than normal PC sound. Then no regular PC sound output can be done. I'm not sure it works that way with nVidia unless it disables normal PC sound output when there is a HDMI connected device. There certainly is no nVidia HD audio device to be selected in the sound device to use like there is with ATI.

It's worth investigating before deciding in which direction to go. How well each system works with HD audio over HDMI.

Hi Def video decoding assistance is possible on ATI as well as nVidia. DirectX video acceleration can providing video decoding assistance with suitable software such as Media player classic home cinema. It could be extras that CUDA could provide with suitable software such as PowerDVD. I don't use PowerDVD so don't know what it is capable of or what extras CUDA offers.

The reason I mentioned consoles is because I realise that some people do on the fly transcoding so that consoles can play back certain files which are available.

Something to look at is vReveal it can enhance video and it can be sped up using CUDA.

GPU encoding is probably best ignored because the tests I did with Badboom trial didn't impress me. Very fast but quality is fairly low.

I have never used Mediacoder so don't know how well it's CUDA encoding works. The opencandy adware isn't going to get installed on this system. I might try it on an old windows install I have which I use for testing.

My GT 240 isn't really up to too much for GPU encoding as it has only 96 CUDA cores so speed wise it's not too impressive. It does very well for HD decoding assistance using DGDecodeNV and AVISynth, decoding as fast as the 400 series GPU's by nVidia. That's because the video processing engine is the same in both, VP4. I haven't seen any number for nVidia's latest but it's probably the same.

A lot to take in, investigate and consider.