Why does a CPU need a GPU?

[Leonidas]

why not make a dualprocessor motherboard with integrated graphics where one processor was just for graphics and 1 GB of DDR550 memory was Graphics memory, even let nvidia design all the interface and everything, having 2.6GHZ AMD 64 pumping out your graphics with 1 gig of highspeed memory has got to be killer...


i do realize in all actuality the quality of the graphics would suck, because a regular CPU is nothing like a gpu... gpu's use programmable vertex shaders and such, so 2.6ghz of regular computational powers cant be converted at all, but perhaps for super amazing highend systems this could be possible, and even better... make it possible to get just faster memory or just faster processor for your graphics.

 

[ak_smallz]

think of the GPU as another processor leo

 

[gimpycow]

I read a good article on this subject from Tim Sweeny of Epic Games. He is the main engineer responsible for the Unreal engines.

As some of you stated, the cpu is not designed specifically to handle graphics...like pixel & vertex shaders, etc. In addition, cpu's have a hard time of multi-threading and keeping the threads in sync. GPU's, on the otherhand, are designed with multiple pipes and all the rendering is synchronized.

Tim Sweeney had indicated that there will come a time with CPU's and GPU's get so powerful that using both will not make sense. It will be at that point that they will probably merge into one.

Personally, I see GPU's outpacing CPU's quickly. Both Intel and AMD are going dual core now because they are reaching the performance ceiling on their single chips. That is not a good thing because games are not developed to be multi-threaded and take advantage of a dual core system. This is why a super computer with 1,000+ slower cpu's might actually play a single-threaded game SLOWER than a faster processor in a regular desktop machine!

I have a feeling for the next year or so, things will be pretty bleak on the cpu front until applications are designed to multi-thread properly. Once that happens, watch out! For the long term, I guess new materials and designs are being researched to increase the performance of single processors.

I don't see CPU's and GPU's merging for quite sometime.

 

[gimpycow]

OH...and the Playstation 3 is using a next-gen graphics chip from Nvidia so I am not sure why the PS3 was used as an example of combining the CPU and GPU into one chip.

Likewise, the XBox 2 is using a next-gen GPU chip from ATI.