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pApA SmerF01
27-07-2005, 11:02 AM
:cheers: :albertein Grindstone wanted me to make another thread detailing the actual TFLOP count (or what i have mathematically calculated) for each system:

the ps3, original statements from sony and fanboys alike put their total system floating point operation count at 2.18.

the only problem with that 2.18 number is that they are counting the impossible idea that their machine is working at 100%.

the real numbers break down like this:

70% of the FLOP count comes from the gpu. the nVidia G70 gpu can (since it isn't usa) only run at best 70% efficiency, so you have to divide into that 2.18 number the difference and then subtract. but don't forget to put about .17 latent (idle, like an inactive volcano) for efficiency and if something goes wrong.

so 70% of 2,180,000 is....1,526,000. now you take that number and subtract 30-50%, depending on how much you trust sony....

i'm taking off 40% which means 60% efficiency...the total number to take off is 610,400. so 1,526,000 - 610,400 is...915,600. now add 654,000 from the cpu and buffering chips you get the "actual" count...

1,569,600 is the count that you get for this modest equation. not 2.18 TFLOPS. plus you have to leave a certain portion latent. so anyone who brings up the TFLOP argument, here's the equation (simple math) to find out the real count.

to talk about efficiency as an absolute is a farce. it's simply impossible to achieve 100% efficiency on any level of engineering. even the xenos processor is at best 98% efficient. any device mechanical or electronic suffers parasidic losses through its own operation. to claim 100% efficiency, you're basically chasing perpetual motion. :tee: :albertein

pApA SmerF01
27-07-2005, 11:15 AM
my friend david made that last analogy. i am trying to get him onto the board...that chump! lol j/k!

he's really, really, REALLY, addicted to metal gear solid 1. poor dave..... :hahaha:

Grindstone
27-07-2005, 12:31 PM
Thanks for the info. Is the reason for the 70% efficiency of the PS3 because of the bandwidth bottlenecking problem or some other architectural flaw?

pApA SmerF01
27-07-2005, 12:42 PM
Thanks for the info. Is the reason for the 70% efficiency of the PS3 because of the bandwidth bottlenecking problem or some other architectural flaw?

when you have separate shader pipelines, ie. vertex and pixel, you have to have the exact same amount of pipelines going for each at the same time, but sometimes they go out of synch and it throws a certain portion "idle". now the only time they're woken up is when one of the pipelines "gives out" or just kinda breaks.

that's where the 70% efficiency comes from, because without unified shader architecture, you really only have 70% of the pipelines working at best.

Grindstone
27-07-2005, 12:53 PM
I take it that they go out of synch often enough for there to be a 30% loss in efficiency. Also, that the unified shader from the ATI gpu does have the exact number of pipelines going at the same time, whereas the nVidia RSX does not which causes the loss in performance. Did I sum that up well enough or am I missing something? The Xbox 360 get ~98% efficiency through the unified sharder, whereas the PS3 gets ~70% becasue of the flawed gpu pipeline design.

pApA SmerF01
27-07-2005, 01:08 PM
I take it that they go out of synch often enough for there to be a 30% loss in efficiency. Also, that the unified shader from the ATI gpu does have the exact number of pipelines going at the same time, whereas the nVidia RSX does not which causes the loss in performance. Did I sum that up well enough or am I missing something? The Xbox 360 get ~98% efficiency through the unified sharder, whereas the PS3 gets ~70% becasue of the flawed gpu pipeline design.

the 98% efficiency comes from the pipelines being able to do both vertex and pixel shading. therefore you don't need an "exact" amount going in synch.

Grindstone
27-07-2005, 01:59 PM
Good! Thanks, I have been educated and I will now destroy my enemies. They shall fear me forever more!

citizen X
27-07-2005, 06:36 PM
Good! Thanks, I have been educated and I will now destroy my enemies. They shall fear me forever more!

By “destroy my enemies” he means slashing their tires, and buying them out like MS does.

Isn’t that right grindstone j/k ;)

Grindstone
28-07-2005, 12:10 PM
Uh, yeah... matter-of-factly. What, you thought I was going to impress them with my knowledge? No, no, I'm much more low-tech than that. Give me a good Gerber blade and a healthy bank account, and I'll win my enemies over.

pApA SmerF01
28-07-2005, 12:14 PM
Uh, yeah... matter-of-factly. What, you thought I was going to impress them with my knowledge? No, no, I'm much more low-tech than that. Give me a good Gerber blade and a healthy bank account, and I'll win my enemies over.

can i give you a tater-tot and a spatula?

look, if you have any techie questions, just come to me or citizen x. we'll more than likely be able to answer it. if n e fanboy's give you a hard time, just invite me in and i'll make them look like chimpanzees(unless it's lupus sheerheart).

citizen X
28-07-2005, 01:45 PM
Uh, yeah... matter-of-factly. What, you thought I was going to impress them with my knowledge? No, no, I'm much more low-tech than that. Give me a good Gerber blade and a healthy bank account, and I'll win my enemies over.


lol :tee:

Sorry for over estimating u. :top:

Your right, in the end that’s what it comes down to, shanking (not shore of the spelling) people's tires. ;)

Good times :D