why no multicore ?

[86JR]

something i cant figure out.... why hasnt nvidia or ati made multi core gpu's yet ? like a q6600 in your gfx card...... lol

 

[Dogoid]

they have.


edit, ok they haven't, but a card like the 4870x2 is what i thought you meant. same deal really but GPUs are inherently parallel, not like CPUs.

if you want, you can see a 'shader' and a 'stream processors' as a simple processor

 

[Schnippzle]

Apparently Larabee is going to be multi-core from the start

 

[tmaxxthomson]

the RV800 dual GPU card is gonna be a a true multi GPU, it will be named like 5870x2 but it wont have 2 seperate cores relying on crossfire, it will be 2 gpus stacked ontop of eachother!

 

[thegoonden]

the RV800 dual GPU card is gonna be a a true multi GPU, it will be named like 5870x2 but it wont have 2 seperate cores relying on crossfire, it will be 2 gpus stacked ontop of eachother!

Does this mean it will be seamless in every game or just the chosen few as with Xfire?


(all right it's not a few, but it's only games that have come out since xfire, and I play some considerably older ones that still buckle my machine with the IQ all turned full up.)

 

[mmj_uk]

Too much heat over a small area I would've thought, just look at Xbox 360 reliability to see where that leads.

 

[Schnippzle]

Too much heat over a small area I would've thought, just look at Xbox 360 reliability to see where that leads.

The majority of 360 failures are more than likely to have been caused by a faulty psu or a badly treated psu. Sure the RROD has plagued the console somwhat......havent actually got an argument for this...

 

[Strife212]

They are multi core, a GPU has hundreds of 'cores'

 

[Crashgate3]

Aren't GPUs massively parallel anyway, so upping cores wouldn't actually do much more than just having a single-core chip that can do twice as much processing?

 

[mmj_uk]

Aren't GPUs massively parallel anyway, so upping cores wouldn't actually do much more than just having a single-core chip that can do twice as much processing?

So what is Crossfire/SLI?

From what I gather OP is asking why are dual-GPU cards 2 separate GPU's rather than 2 cores integrated into one die.

Judging by 4870x2 heat would be far too much of a problem, with separate GPU's there is greater surface area to dissipate heat, it is probably also cheaper to just design a PCB for current GPU's rather than to put R+D into integrating 2 cores into a single die.

 

[Crashgate3]

So what is Crossfire/SLI?

Exactly what I said. It's no different to having everything grouped together into one big chip, wheras a a dual-core CPU is significantly different to a (hypothetical) big single-core CPU.

 

[Duff-Man]

Modern graphics cards are effectively (massively) multi-core anyway. You have hundreds of individual processors each acting in parallel, sharing a small cache with a few other processors, and sharing a common memory with all the other processors on the silicon. this is exactly the same as modern multi-core processors, except that the GPU has many hundreds instead of 4 (and the processors are limited in their scope).

The "multi-GPU" setups are different from the above, because they draw from different memory banks. This is both the strength and weakness of multi-GPU systems; the different memory banks allow an (almost) doubling of memory bandwidth. However they also require twice as much memory to achieve the same effect, and also lead to communication latencies (which can reduce performance and lead to such phenomena as microstutter).


Hence, a good analogy is:
* GPU = shared-memory cluster [like a multi-core CPU or multi-processor machine]
* multi-GPU setup = distributed-memory cluster