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HBM Power savings vs. GPU

TaintedSquirrel

TaintedSquirrel

[H]F Junkie
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Note: This might sound like a rumor thread but I actually just have a question about VRAM vs GPU power consumption.

So, let's assume HBM on the new flagship will save precisely 50W under peak gaming loads.
We'll also use the 290X's power consumption, about 290W, as a starting point. So now we have a 390X card that uses approximately 240W under load. That's great, 50W less than the 290X and about the same as the Titan X!

Now let's say all of the additional shaders and no new arch improvements have pushed the GPU up 50W. So now the total video card power usage is back to 290W again.

So, previously, we had a 290X GPU that used let's say 200W (+90W GDDR5).
Now we have a 390X GPU that uses 250W (+40W HBM).
However if you bench both cards, they will show the same amount of power at the wall (290W). But that load has now shifted from the ram chips to the GPU itself.

So... What does this mean for overall video card performance? Lower stability? Lower OC headroom? Higher temps than Hawaii?
Isn't this considered cheating, maybe? Shifting power usage from memory to GPU won't show any effects in benchmarks but will have HUGE negative side-effects.

All of the past leaks point to a ~290W 390X and people have been saying "No big deal it's the same as the 290X" but considering the changes in power usage, could it be a bigger problem than before?
 
TaintedSquirrel said:
So... What does this mean for overall video card performance? Lower stability? Lower OC headroom? Higher temps than Hawaii?
Isn't this considered cheating, maybe? Shifting power usage from memory to GPU won't show any effects in benchmarks but will have HUGE negative side-effects.

All of the past leaks point to a ~290W 390X and people have been saying "No big deal it's the same as the 290X" but considering the changes in power usage, could it be a bigger problem than before?
Click to expand...

No. No. No.
No.
Please explain how "shifting power usage from memory to GPU won't effect benchmarks but have HUGE negative side-effects."

No.

What you aren't taking into account is process variation and design goals.
TSMC 28HP is different from 28HPM and very different from GF 28SHP (or FD-SOI).

Using your numbers 200w/438mm2 = .457w/mm2 (though not entirely accurate since power consumption isn't evenly distributed across the chip.)
250w/~550mm2 = .455w/mm2
So the actual power density of just the GPU is actually less than Hawaii.

Not to mention there will be additional power gating and better voltage control in Fiji when compared to Hawaii.

Edit- Did GK104 have problems because it had a ~170w GPU TDP in a 294mm2 die vs Tahiti with a ~180w GPU TDP in a 365mm2 die or Hawaii with a 200w GPU TDP in a 438mm2 die?
 
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Less power demands with ram then you can add more die stuff to achieve more performance.
HBM is just a new tech coming to GPU/CPU.

The recent development are to add more control to power regulating it more efficiently.
Which means you can have a 300w but in reality you see much less in actual use as the power regulates better and faster like the 980 for example who use same power as a 290x but regulates it more efficiently.
Power regulating tech is going to be better for 390x than previous generation.

https://www.youtube.com/watch?v=twk-0On2Exg#t=643
 
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TaintedSquirrel said:
Note:
05a.jpg
Click to expand...


Bad math, bad deduction and bad conclusion.

The GPU will be a more efficient chip and have more power available to drive it due to less power used in HBM. So it will also overclock well. Given the rumors are true.


Why not be honest and come out and say that you want it to fail?
 
Flopper said:
Less power demands with ram then you can add more die stuff to achieve more performance.
HBM is just a new tech coming to GPU/CPU.

The recent development are to add more control to power regulating it more efficiently.
Which means you can have a 300w but in reality you see much less in actual use as the power regulates better and faster like the 980 for example who use same power as a 290x but regulates it more efficiently.
Power regulating tech is going to be better for 390x than previous generation.

https://www.youtube.com/watch?v=twk-0On2Exg#t=643
Click to expand...


cool, thanks for sharing... very informative!
 
My bet is AMD top dog GPU flagship slots in just under Titan X in performance, 10-15% slower making AMD to price it ~$700 until Nvidia responds with a 980Ti that will sit somewhere between that and the Titan X at that same $700 price point, forcing AMD to drop prices. GTX 980 drops to maybe $500 or so. 970 stays in that $300-330 range, and AMD's new parts are priced accordingly.
 
lukart said:
My bet is AMD top dog GPU flagship slots in just under Titan X in performance, 10-15% slower making AMD to price it ~$700 until Nvidia responds with a 980Ti that will sit somewhere between that and the Titan X at that same $700 price point, forcing AMD to drop prices. GTX 980 drops to maybe $500 or so. 970 stays in that $300-330 range, and AMD's new parts are priced accordingly.
Click to expand...

I will take your bet.
390 will beat Titan. Maybe not much but beat it.
Then what?

Its all speculation.
 
There used to be a saying, like back when the Geforce 256/Geforce 2 came out .. nVidiot. Seems like it should come back... lol

390x (Which will actually be called 490x...) will be sold for $549-599
 
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