SSE2 Question

[TheOriginalTaco]

I think its kinda funny how i noticed this but i was playing minecraft (lol) and i pressed F3 on the right it said  GTX 970 PCIe SSE2 and i was curious what SSE2 was (love learning new things) so i googled it. i was very unhappy with what my search turned up

 

 

"SSE2, Streaming SIMD Extensions 2, is one of the Intel SIMD (Single Instruction, Multiple Data) processor supplementary instruction sets first introduced by Intel with the initial version of the Pentium 4 in 2001. It extends the earlier SSE instruction set, and is intended to fully replace MMX. Intel extended SSE2 to create SSE3 in 2004. SSE2 added 144 new instructions to SSE, which has 70 instructions. Competing chip-maker AMD added support for SSE2 with the introduction of their Opteron and Athlon 64 ranges ofAMD64 64-bit CPUs in 2003."

 

what the hell? pentium 4 is ancient!! I am so confused what is sse3? an extension of sse2? sse3 has 13 more instructions than sse2. what does that even mean? instructions? what does this have to do with my graphics card? Somebody please explain...

 

(i assumed it had something to do with my gpu because it sad GTX 970 PCIe SSE2)

 

[Casperian]

Instructions are the binary that CPUs understand. So in assembly, the command "add $1,$2,$3" (Adds the content of register 3 to register 2 and stores result in register 1) will assemble to a 32bit binary "instruction" that the CPU can decode and run.

AFAIK GPU's don't use SSE at all, NVidia Cuda uses the PTXAS instruction set

[TheOriginalTaco]

Instructions are the binary that CPUs understand. So in assembly, the command "add $1,$2,$3" (Adds the content of register 3 to register 2 and stores result in register 1) will assemble to a 32bit binary "instruction" that the CPU can decode and run.

AFAIK GPU's don't use SSE at all, NVidia Cuda uses the PTXAS instruction set

not sure i follow you. this does not matter for my gpu because it uses a entirely different instruction set?  

[harrynowl]

Don't take my word for it as I've never looked into it, but I was told it was used within PhysX.

[mathijs727]

not sure i follow you. this does not matter for my gpu because it uses a entirely different instruction set?

I think it's an error in the way minecraft displays the information.

It has nothing to do with your GPU but rather is an instruction set for your CPU.

It was eveloped by intel but had been adopted by AMD (like x68/AMD64 has been developed by amd and adopted by intel).

An instruction set is a collection of instructions that a processor might execute.

An instruction is an array of bits (0 or 1) that the processor will have to understand. An example could be adding or subtracting values.

The regular x86 instructions all do a single calculation at a time (1 addition for example or 1 substraction). We call this principle SISD (Single Instruction Single Data) and its what cpu's are really good at.

SSE stands for Streaming SIMD extension and as the name tells you it are some extra instructions to extend the x86 instructionset.

But these are not normal instructions, they are SIMD: Single Instruction Multiple Data.

That means that one instruction can do multiple (but the same type of) operations.

In case of SSE you can do 4 of the same operations with one instruction. The cpu also has to contain special 128 registers (a place to save values like in RAM but build into your cpu and wayyyyyyyyy faster). The advantage of using SSE is that it will be faster to execute the SSE instruction than it is to execute 4 regular x86 instructions.

To take advantage of SSE you have to write some special code in your program (like minecraft does).

Most games use SSE as it is perfect for vector calculations (linear algebra).

Sorry if he post is a mess i dont have access to my pc only a phone ;(