AMD Makes An Evolutionary Leap In Linux Support

[he_the_great]

Bridgman, I think that was pretty much I was afraid of. Seems a little narrow minded, hopefully they have bigger plans for later.

[Kano]

Both nvidia + ati hybrid solutions are pretty much useless. A real gamer will never buy a lowend gfx card and bundle it with an onboard solution. Even when it technically works, the speed is much slower then the midrange gfx card series. So the real question is how need the minimum higher performance compared to pure onboard and does not need the performance of the higher level gfx cards? I think absolutely nobody - maybe as marketing gag for cheap systems with SLI or Crossfire sticker on em...

[he_the_great]

Your right who needs dual core when you can have 1 core that is just as fast as the dual combined. As for what it is right now I would agree that it is not worth it, but if it was what I expect, 2 gfxs cards working as together without needed to be the same performance, then I would be great. on another Note, I don't think CrossFire is worth it either.

[bridgman]

Bridgman, I think that was pretty much I was afraid of. Seems a little narrow minded, hopefully they have bigger plans for later.

Just to be clear, I'm not saying "we can't support it" I'm saying "it's not a very good idea"

The multi-gpu overhead can cost you as much or more as you get from the slower GPU. Remember that we have perhaps 8:1 performance difference between high end and low end cards, eg 320 ALUs in a 3870 vs 40 ALUs in a 3450 or 780.

AFAIK we already support mismatched cards in CrossfireX but we try to only enable it in cases where you get an actual improvemt.

[some-guy]

Your right who needs dual core when you can have 1 core that is just as fast as the dual combined. As for what it is right now I would agree that it is not worth it, but if it was what I expect, 2 gfxs cards working as together without needed to be the same performance, then I would be great. on another Note, I don't think CrossFire is worth it either.

Dual Core has each core in parallel processing, so each core does a different chunk, this is what makes it better

[mtippett]

A couple of clarifications.

Hybrid Crossfire

Hybrid Crossfire requires two 3D cores of the same class. In this case the 780G and HD 3840 have a common core (RV610/RV620). This is so the Crossfire approach can work.

In terms of performance, Hybrid Graphics is not intended for hardcore gamers. It is for the entry-level or casual gamer. The person who bought a $700 desktop system with a 780G, and decide that a $50 upgrade for a second card will allow them to game at around 1280x1024 with current mainstream games.

The 3840 upgrade
Some Hybrid Crossfire Benchmarks

In general, Crossfire has greatest scaling when the graphics hardware is the limiting factor. This results in Hybrid Crossfire (780G + HD3840) having high scaling (as per the benchmarks)

CrossfireX

CrossfireX is still what is called Symmetric Crossfire which means two matching families of cards running together. This usually means any of the HD38x0 family.


As per Michael's article on the RV770, we can confirm that Crossfire is coming for the HD 4850 family. As for the other modes as discussed, they are obviously not currently supported.

Regards,

Matthew

[Kano]

The benchmarks are really poor, when you are used to faster gfx cards (funnyly not even one faster card was added for comparision). And several games do not profit from Crossfire as you can see... It is a useless buy when only 50% or less games really get more speed and the rest are as slow as before. A good buy would increase speed of ANY game.

[duby229]

The only thing that I want to add to this conversation is that in the near future most AMD users will have an integrated video card on the motherboard. Even harcore enthusiasts and gamers. The integrated video card will become standard.

With this in mind it might be a good idea to use the integrated video card during low load scenarios, then switch to the discreet card when a higher load occurs. This will require driver support. Another possibility is to use the integrated gpu for general purpose code. This should already be possible with Brook+, nowe we just need to get enough idle gpu's into the market to convince programmers that it is worth there time to port there software.

[Kano]

Yes, thats another way. I think Nvidia implemented this already - but you have to manually switch between onboard + dedicated card. Switching needs 5s - did not try myself, just read about that in ct (german pc magazin). I have no info when that will be possible with Linux.

[zappa86]

This makes me feel bad for getting an Nforce 780a motherboard and a GF8800GTS G92 to go with my new phenom. I stuck in an old ATI card and the Linux drivers are much better then they used to be. My next comp will be all AMD/ATI.