No they don't, at least on the Pentium 4, it takes 2 clock cycles to complete a SiMD instruction (I realise SiMD is many instructions at once but you know what I mean). Right now they've mananged to get their SiMD unit to 1.4Ghz while the cpu runs at 2.8. Personally speaking if motorola did this to the G4 and it meant we could have a 2Ghz G4 with the altivec performance of a 1Ghz G4 then that's a good thing, Altivec only helps speed up certain operations, a faster cpu speeds up all operations.
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The future of the G3
- Thread starter mr evil brkfast
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No they don't, at least on the Pentium 4, it takes 2 clock cycles to complete a SiMD instruction (I realise SiMD is many instructions at once but you know what I mean). Right now they've mananged to get their SiMD unit to 1.4Ghz while the cpu runs at 2.8. Personally speaking if motorola did this to the G4 and it meant we could have a 2Ghz G4 with the altivec performance of a 1Ghz G4 then that's a good thing, Altivec only helps speed up certain operations, a faster cpu speeds up all operations.
barkmonster:
I don't have a link handy about the actual speed at which SSE/SSE2 operates, but I'll try to get back to you on that.
I don't have a link handy about the actual speed at which SSE/SSE2 operates, but I'll try to get back to you on that.
Actually SIMD stands for Single Instruction Multiple Data, so as you can see it is not many instructions at once, only mulitple hunks of data at once. It is accurate to say that a SIMD instruction does the work of multiple "normal" instructions.
keep the G3 processor for the crt imac and constantly up its speed from time to time while lowering it $699, 599, and finally 499 usd
use the G3fx in the ibook until mwsf in january 2003...and then put in a G4 at that time
at the end of 2003, then pull the G3 from the crt imac and put a G4 in it and keep it as an educational and entry level mac
hopefully, sometime in 2003 and certainly by the end of that year, we will have the G5 in pro model towers
wishful thinking...i know, but it's a goal to shoot for (if crt imac goes to $599 usd and ibook gets G4 in mid-2003...that will actually not be bad, either)
use the G3fx in the ibook until mwsf in january 2003...and then put in a G4 at that time
at the end of 2003, then pull the G3 from the crt imac and put a G4 in it and keep it as an educational and entry level mac
hopefully, sometime in 2003 and certainly by the end of that year, we will have the G5 in pro model towers
wishful thinking...i know, but it's a goal to shoot for (if crt imac goes to $599 usd and ibook gets G4 in mid-2003...that will actually not be bad, either)
imac G3 sales
I would be interested to hear how the old imac is selling. If it is selling well enough - Apple should continue by all means to keep it in the lineup- at least until it can get the emac price under $1000 US.
It wouldn't be too hard to up it to 700mhz and drop the price (one would think) to $699. I dunno about dropping a G4 in the model when you have the emac already.
I would love to see an under $1000 CDN mac- about $629 US.
I would be interested to hear how the old imac is selling. If it is selling well enough - Apple should continue by all means to keep it in the lineup- at least until it can get the emac price under $1000 US.
It wouldn't be too hard to up it to 700mhz and drop the price (one would think) to $699. I dunno about dropping a G4 in the model when you have the emac already.
I would love to see an under $1000 CDN mac- about $629 US.
barkmonster:
I have done some research and discussed with some people and I think that in the end the P4's SIMD abilities are not implemented in the same way as those on the G4. Specifically, although Intel is not very up-front about it, there may not even be "SSE units" like there is an AltiVec unit. The SSE instructions may simply be ran through the same hardware the runs the normal instructions, except that since a single SIMD instruction means a lot more, the P4 is able to achieve higher efficientcy by using them over the standard code.
In the end it is not accurate to say that the P4 runs it "SIMD unit" at 1.4ghz or any other speed, because it just isn't clear what exactly is the SIMD unit and what is the rest of the processor. It's all squished together.
It is clear that AltiVec can do more per clock, but I can't say how much more and in what situations. Answering that will require a lot of research, and this is the weekend.
I have done some research and discussed with some people and I think that in the end the P4's SIMD abilities are not implemented in the same way as those on the G4. Specifically, although Intel is not very up-front about it, there may not even be "SSE units" like there is an AltiVec unit. The SSE instructions may simply be ran through the same hardware the runs the normal instructions, except that since a single SIMD instruction means a lot more, the P4 is able to achieve higher efficientcy by using them over the standard code.
In the end it is not accurate to say that the P4 runs it "SIMD unit" at 1.4ghz or any other speed, because it just isn't clear what exactly is the SIMD unit and what is the rest of the processor. It's all squished together.
It is clear that AltiVec can do more per clock, but I can't say how much more and in what situations. Answering that will require a lot of research, and this is the weekend.
I still believe that I read somewhere that the Altivec units were a big part of the Mhz hold back on the G4.
MacBandit:
Of course you could have read it somewhere.
If the G4 is well designed (which I think is true), most of the parts are finding their max speed at more-or-less the same time. Otherwise some parts have too much headroom, and hence are probably a waste of resources.
Of course you could have read it somewhere.
If the G4 is well designed (which I think is true), most of the parts are finding their max speed at more-or-less the same time. Otherwise some parts have too much headroom, and hence are probably a waste of resources.
Originally posted by ddtlm
MacBandit:
Of course you could have read it somewhere.
If the G4 is well designed (which I think is true), most of the parts are finding their max speed at more-or-less the same time. Otherwise some parts have too much headroom, and hence are probably a waste of resources.
Okay okay I get the point. My problem is I read too much. I know this. I do filter a bunch of the crap out. My biggest problem is when I remember something of relevence and I just can't recall where I read it.
