Hi all, this forum has some of the best tech heads I've seen so I am posting this here. I am hoping you guys could clarify this for me. I recently came across this:
http://www.firingsquad.com/features/xbox_360_interview/default.asp
"We have 48 shaders. And each shader, every cycle can do 4 floating-point operations, so that gives you 196.
The 192 is actually in our intelligent memory, every cycle we have 192 processors in our embedded intelligent memory that do things like z, alpha, stencil. So there are two different numbers and they’re kind of close to each other, which leads to some confusion. "
http://www.techreport.com/etc/2005q2/xbox360-gpu/index.x?pg=1
"On chip, the shaders are organized in three SIMD engines with 16 processors per unit, for a total of 48 shaders. Each of these shaders is comprised of four ALUs that can execute a single operation per cycle, so that each shader unit can execute four floating-point ops per cycle."
http://www.techreport.com/etc/2005q2/xbox360-gpu/index.x?pg=1
"On chip, the shaders are organized in three SIMD engines with 16 processors per unit, for a total of 48 shaders. Each of these shaders is comprised of four ALUs that can execute a single operation per cycle, so that each shader unit can execute four floating-point ops per cycle.
Basically, there's a 10MB pool of embedded DRAM, designed by NEC, in the center of the die. Around the outside is a ring of logic designed by ATI. This logic is made up of 192 component processors capable of doing the basic math necessary for multisampled antialiasing. If I have it right, the component processors should be able to process 32 pixels at once by operating on six components per pixel: red, green, blue, alpha, stencil, and depth. This logic can do the resolve pass for multisample antialiasing right there on the eDRAM die, giving the Xbox 360 the ability to do 4X antialiasing on a high-definition (1280x768) image essentially for "free"—i.e., with no appreciable performance penalty. The eDRAM holds the contents of all of the back buffers, does the resolve, and hands off the resulting image into main system memory for scan-out to the display. "
http://www.anandtech.com/tradeshows/showdoc.aspx?i=2423&p=2
"The daughter die is where the 10MB of embedded DRAM resides, but there is also a great deal of logic on the daughter die alongside the memory. The daughter die features 192 floating point units that are responsible for a lot of the work in sampling for AA among other things."
So... does that mean that:
48 ALU's performing 4 ops per clock, and 192 vector units performing an additional 1 op per clock on the data in the 10MB EDRAM.
= 192 Billion operations per second?
contrary to what MS has released previously? Wouldn't mean that the gpu is really advanced and a monster? Thanks!
http://www.firingsquad.com/features/xbox_360_interview/default.asp
"We have 48 shaders. And each shader, every cycle can do 4 floating-point operations, so that gives you 196.
The 192 is actually in our intelligent memory, every cycle we have 192 processors in our embedded intelligent memory that do things like z, alpha, stencil. So there are two different numbers and they’re kind of close to each other, which leads to some confusion. "
http://www.techreport.com/etc/2005q2/xbox360-gpu/index.x?pg=1
"On chip, the shaders are organized in three SIMD engines with 16 processors per unit, for a total of 48 shaders. Each of these shaders is comprised of four ALUs that can execute a single operation per cycle, so that each shader unit can execute four floating-point ops per cycle."
http://www.techreport.com/etc/2005q2/xbox360-gpu/index.x?pg=1
"On chip, the shaders are organized in three SIMD engines with 16 processors per unit, for a total of 48 shaders. Each of these shaders is comprised of four ALUs that can execute a single operation per cycle, so that each shader unit can execute four floating-point ops per cycle.
Basically, there's a 10MB pool of embedded DRAM, designed by NEC, in the center of the die. Around the outside is a ring of logic designed by ATI. This logic is made up of 192 component processors capable of doing the basic math necessary for multisampled antialiasing. If I have it right, the component processors should be able to process 32 pixels at once by operating on six components per pixel: red, green, blue, alpha, stencil, and depth. This logic can do the resolve pass for multisample antialiasing right there on the eDRAM die, giving the Xbox 360 the ability to do 4X antialiasing on a high-definition (1280x768) image essentially for "free"—i.e., with no appreciable performance penalty. The eDRAM holds the contents of all of the back buffers, does the resolve, and hands off the resulting image into main system memory for scan-out to the display. "
http://www.anandtech.com/tradeshows/showdoc.aspx?i=2423&p=2
"The daughter die is where the 10MB of embedded DRAM resides, but there is also a great deal of logic on the daughter die alongside the memory. The daughter die features 192 floating point units that are responsible for a lot of the work in sampling for AA among other things."
So... does that mean that:
48 ALU's performing 4 ops per clock, and 192 vector units performing an additional 1 op per clock on the data in the 10MB EDRAM.
= 192 Billion operations per second?
contrary to what MS has released previously? Wouldn't mean that the gpu is really advanced and a monster? Thanks!
