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MBA 2011 13" TDP: 17 vs 25 watt
- Thread starter Vazkor
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You must also think of that theres a difference in cooling needed for these draws. If the CPU draws more then a more powerful CPU cooler is needed and so on. Might be that the higher wattage ones might be give too high a heat emission on the area. But yeah, 17W they might be able to include.
I think in the end, SB might use a little lower voltage than the current C2D and 320m combo, but the heat is going to be MUCH greater.
MBP (although it uses a Standard Volt.) gives enough heat for people to complain, the ULV might affect the already thin machine to heat up really quick.
MBP (although it uses a Standard Volt.) gives enough heat for people to complain, the ULV might affect the already thin machine to heat up really quick.
this has been discussed before, however, with no mention of 25W CPUs in the recent rumors, i've started to wonder myself.
TOTAL TDP
many of us, i think, have been taking it as granted that Apple would do:
11" = 17W
13" = 25W
when accounting for the 320M, (which must be estimated, ~10W, let's say), total TDPs in the current model are under those above, so its seemingly quite doable.
also note:
2010 13 MBP = 25W CPU + (10W?) 320M
2011 13 MBP = 35W CPU/IGP combo
HEAT DISTRIBUTION?
now, this issue has been brought up as well, something i overlooked myself initially; even though the (total) TDP may not increase, its all in one spot now, making it harder to get rid of. if the 2011 13 pros really are hotter, this may be why.
i am not an expert, so i cant really comment on this. has this issue been addressed?
DESTINED TO BE AN AIRHEAD?
of course, the current Airs are plenty for many users and the new ones should be even more capable (games aside), so i wouldn't quite call the Air an airhead, but the update means, to me, and maybe to others, that the air will finally be a 'regular computer', as far as (CPU) power goes; no more need for comments like:
" ... but she has a great body"
however, the difference between a 17W and a 25W 13" is pretty big. with a 25W CPU, it would be about as smart as a 13 MBP. (no?) with a gross low res screen, and extra baggage, the pro starts to look like the less attractive sister, (though, sure, it retains better upgradeability, etc.)
would Apple dumb the Air down to separate the lines? ... me not know.
anyways, wish i knew. i might buy a 13 MBP if i knew it was going to be 17W. i had actually just been thinking about making a poll for this; (hadn't decided if it was a good idea)
Mobile Sandy Bridge CPUs
(note: 17W is the minimum!)
TOTAL TDP
many of us, i think, have been taking it as granted that Apple would do:
11" = 17W
13" = 25W
when accounting for the 320M, (which must be estimated, ~10W, let's say), total TDPs in the current model are under those above, so its seemingly quite doable.
also note:
2010 13 MBP = 25W CPU + (10W?) 320M
2011 13 MBP = 35W CPU/IGP combo
HEAT DISTRIBUTION?
now, this issue has been brought up as well, something i overlooked myself initially; even though the (total) TDP may not increase, its all in one spot now, making it harder to get rid of. if the 2011 13 pros really are hotter, this may be why.
i am not an expert, so i cant really comment on this. has this issue been addressed?
DESTINED TO BE AN AIRHEAD?
of course, the current Airs are plenty for many users and the new ones should be even more capable (games aside), so i wouldn't quite call the Air an airhead, but the update means, to me, and maybe to others, that the air will finally be a 'regular computer', as far as (CPU) power goes; no more need for comments like:
" ... but she has a great body"
however, the difference between a 17W and a 25W 13" is pretty big. with a 25W CPU, it would be about as smart as a 13 MBP. (no?) with a gross low res screen, and extra baggage, the pro starts to look like the less attractive sister, (though, sure, it retains better upgradeability, etc.)
would Apple dumb the Air down to separate the lines? ... me not know.
anyways, wish i knew. i might buy a 13 MBP if i knew it was going to be 17W. i had actually just been thinking about making a poll for this; (hadn't decided if it was a good idea)
Mobile Sandy Bridge CPUs
(note: 17W is the minimum!)
They will continue to use the 17w cpu. They will advertise it as the longest battery in the business. If you need more processing power, then you must go to the MBP.
That's quite an interesting analysis. But I think a lot of us expect a 17W TDP for the new Air.
someone proposed this idea before, that using 17W as opposed to 25W would increase battery life (dramatically).
i believe it was HH that said this argument isn't quite so simple, as a CPU underclocks itself when idle.
would using 17W as opposed to 25W make a big difference in battery life???
From what people said about 2011 to 2010 in both heat and noise the 2011 model could feel hotter and the fan noise is higher. This is most likely due to the heat emission comming from a smaller area. I think we'll see the same for the MBA, especially since the SB processors can draw lots of power when in Turbo mode.
It's going to be a ULV version of the SB iCores. It probably won't nearly as bad as the MBP is heat eise (not that bad, everyone over hypes the heat)
Theres an ULV version in the MBA right now. The difference between MBA 2011 and MBA 2010 will most likely be comparable to the difference observed between the MBP 2011 and the MBP 2010.
Turbo Boost doesn't draw more power. The whole point is to overclock the only cores that are active, while staying within the TDP. Intel details its mechanics on this page.
How about reading your own links?
"Note: Intel Turbo Boost Technology 2.0 allows the processor to operate at a power level that is higher than its rated upper power limit (TDP) for short durations to maximize performance."
The only rumor we have is Sandy Bridge, there hasn't been any rumors about the detailed specs. The speculations have just been editors' guesses and frankly, they don't really have a clue what they are talking about.
Sony Vaio Z and Lenovo X1 are about as thin as MBA and the Sony is actually even lighter, yet they use standard voltage chips (35W) so if Apple can't fit 25W in MBA, then there is a big problem in the R&D unit.
Sandy Bridge chip is actually quite bit, much bigger than C2D. I did some calculations here. Note that they are package sizes, not die sizes so they aren't very good for this heat comparison but the package size is usually dependent on the die size.
This whole heat thing is moot because nobody can know it beforehand. Apple can always improve the cooling system too.
Yeah, SpeedStep. This is actually evident in current MBAs already. The 11" MBA obviously has a smaller battery but it also has a 10W CPU so why doesn't this compensate the battery life? Shouldn't 11" and 13" have the same battery life because the CPU depends on the battery size? Well, we all know that 11" gets 5 hours and 13" gets 7 hours. Why? SpeedStep.
That "short durations" is a matter of miliseconds, nothing more. A current day Intel processor will run at its rated TDP 99.99999999999% of the time, even in extremely taxing workloads.
What is that difference though? Anyone know? Is it increased noise from the cooling fan?
That's what I've read in reviews. The noise in idle is just a bit higher, but the noise under load is much higher. I am allergic to noise so I feel quite offset by this. I spent much money on my HTPC to make the fans silent.
well, while most of the rumors are not more specific than 'SB + TB', there has been a bit of chatter about the new ULV CPUs (17W), always with the line " ... these are likely to make their way into the new Airs."
i have been essentially ignoring this, as, for one, i agree that a lot of these people don't know what they're talking about, and also, i just think "duh. yes, the 11" will obviously use a ULV. so?"
but, as time has passed, i've begun to wonder if Apple might go all ULV after all.
of course, a good guess comes down to technical considerations: what would they gain by doing that? ... more battery life? better heat management?
there may also be marketing considerations: would a 25W LV MBA be too fast, (making the 13 MBP pointless)?
good point.
well, i guess bigger is better at least, for heat.
of course. however, we do have the 2010 -> 2011 13 MBP to look back at. i don't know if they changed the cooling system much (aside from bigger globs of thermal paste and different fan settings ... which is the noise a lot of people complain about).
well, of course, the 11/13 has a smaller/bigger battery and lower/higher wattage CPU, but its a proportion argument, so its not obvious, unless you're familiar with the specific capacities of the batteries, and even that would mean nothing to me.
... but anyways, to be clear, you think there's nothing (significant) to gain in battery life by using 17W vs 25W in the 13 MBA?
Yeah, the lower TDP CPU shouldn't provide much greater battery life. Apple could have gone with ULV in 13" already but they have decided not to, thus I see no reason to do the switch now.