What is CUDA ?

Marcuskac

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I dont know what it is.
I just know that if the card has more of it is better.Or is it?

Can somebody tell me what are "CUDA cores" for and how does it affect the
performance of the card.

For example should i get the EVGA GTX 670 2GB FTW (It has more memory and clock speed)
or the Gainward GTX 690 2GB (Has more CUDA cores or whatever it is)

Dont look at the price just tell me which is faster and in what cases.

Thanks in advance :D
 
Solution
CUDA is very similar in nature to cores in a CPU. You might have a dual or quad-core CPU, and that is the closest analog to CUDA cores that most people will have any experience with.

However, CUDA cores tend to be more specialized for stream processing as opposed to generalized like a CPU, so there's less logic to duplicate making it easier to fit more CUDA cores onto a GPU.

That said, CUDA's primary use seems to be for allowing the GPU to be used for more general purpose tasks, like encoding videos, or even hardware acceleration of video decoding. For gaming, I would go more for things like memory bus bandwidth, as well as memory and GPU clock speeds. If you can find a card that also has more CUDA cores compared to a very similar...

cl-scott

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CUDA is very similar in nature to cores in a CPU. You might have a dual or quad-core CPU, and that is the closest analog to CUDA cores that most people will have any experience with.

However, CUDA cores tend to be more specialized for stream processing as opposed to generalized like a CPU, so there's less logic to duplicate making it easier to fit more CUDA cores onto a GPU.

That said, CUDA's primary use seems to be for allowing the GPU to be used for more general purpose tasks, like encoding videos, or even hardware acceleration of video decoding. For gaming, I would go more for things like memory bus bandwidth, as well as memory and GPU clock speeds. If you can find a card that also has more CUDA cores compared to a very similar card, then even better, but I'd put CUDA cores a ways down on the list for gaming.
 
Solution

Marcuskac

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But what if i am editing videos and 3d modeling?
Does it render or preview faster with more CUDA cores?
 
CUDA is nVidia's graphics programming language, it is nVidia only and is used to run physX on GPUs and other parallel tasks can be offloaded or written for the GPU using it.


A CUDA core is nVidia's term for one of their graphics processing cores, AMD calls them stream processors, the basic concept is similar between both but the implementation is very different. Generally the lower end cards are based off the same chip as the flagship card but have a fair amount of their CUDA cores disabled, in these cases more cores means more performance which tends to be the case(note: don't compare between product lines! CUDA cores in 4xx, 5xx, and 6xx cards all provide different levels of performance!)

The GTX 690 is an interesting comparison, particularly because it is actually two GTX 680s put onto a single card, unfortunately for most cases where you would need 2 680s on a single card the 2GB of VRAM on the card will limit it since it is split 1GB for one and 1GB for the other. Most of the time the 690 would give much better performance(assuming no CPU limitations), but when you get to higher resolutions and start turning up AA you start needing more and more memory, around 8x AA @ 1920x1080 the 690 would start to hit memory limits and the 670 might scoot ahead. A 4GB 690 won't have problems with anything you throw at it, it is just that some scenarios can make full use of just 1GB of VRAM per GPU.
 

lt_dan_zsu

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CUDA cores in general mean better performance but yes the 690 is about 4 times more powerful than the 670. They are hard to explain you would need to talk to a computer engineer to fully understand what they are but essesntially they are the proccessing units if a GPU. Think of it like this. A 4 core 3 GHz CPU is in stronger than a 2 core 3.4ghz. So yes the 690 is much more powerful. When looking at Mhz of a GPU only look at it between two of the same GPU. The best way to gauge power between two GPUs is CUDA cores/ stream processors. Just think more CUDA cores trumps all. The best way to gauge power between two cards is probably the price difference and looking at benchmarks.
 

motorneuron

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I won't repeat the correct information that others have provided except to note that graphics workloads tend to be much more parallel than other workloads. That's why GPUs have so many CUDA cores/stream processors.

But that isn't really the point anyway. Just look at benchmarks. Also, video cards generally scale in a predictable way. The higher-end, more expensive cards just have more of everything than the lower-end cards. Within a given line of cards, it's not like some cards are good at some tasks, and others are better at others. The better ones are just better. So the question isn't whether the 690 is better than the 670--it is--but rather how much better, and how much that extra performance will cost you. (Of course it's different comparing different lines of cards, or AMD cards to nvidia cards.)
 
http://www.nvidia.com/object/cuda_home_new.html

CUDA™ is a parallel computing platform and programming model invented by NVIDIA. It enables dramatic increases in computing performance by harnessing the power of the graphics processing unit (GPU).

CUDA basically allows you to offload CPU tasks to the GPU....Adobe's Mercury Playback Engine, Sony Vegas and hi end scientific apps make great use of it as it greatly accelerates computations.

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

As far as faster.....I'd have to ask "in what" ?

 

paddys09

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Just as a side note though, I was talking with someone in a thread the other day and we were unable to get the mercury engine to recognize the 6xx series. Works fine with mine though 5xx series, Im sure theyll fix it soon, couldnt find much info on it.