The MacBook Pro Review (13 & 15-inch): 2011 Brings Sandy Bridgeby Anand Lal Shimpi, Brian Klug & Vivek Gowri on March 10, 2011 4:17 PM EST
- Posted in
- MacBook Pro
- Sandy Bridge
Thermals and Power Consumption
The new MacBook Pros have the potential to draw more power than the previous generation. Despite being built on a 32nm process, the new 15 has twice the cores of last year's model—there's no question that it can draw more power under a full load.
I measured maximum power consumption at the wall using the same power brick and a fully charged battery. I chose two high-load scenarios: Cinebench 11.5 and Half Life 2. The former will fully load all CPU cores while the latter ramps up CPU and GPU usage.
Under Cinebench the new quad-core 15-inch MacBook Pro draws 70% more power at the wall than last year's dual-core model. This shouldn't be surprising as Cinebench scales nearly perfectly with core count—twice the cores should result in nearly twice the power draw. The scaling isn't perfect since we are dealing with different architectures and a number of factors such as display remain static. The new 13-inch MacBook Pro isn't as worrisome, it has 88% of the power usage of the high end 2010 15-inch MBP and 81% of the battery capacity.
The Half Life 2 comparison is not quite as bad, although the new 15-inch MBP still uses 45% more power under full load compared to the previous generation. These numbers tell you one thing: although the new MBP is significantly faster than its predecessor, it can also draw significantly more power. Running the same workload the new MBP shouldn't have any problems lasting as long as the old MBP on battery, but running a more aggressive workload will result in shorter battery life as a result of the higher max power consumption. In other words if you use the higher performance to do more, you can expect your battery to last proportionally less than the 2010 MBP.
The 15-inch MBP uses an 85W power adapter (left) and the 13-inch MBP uses a 60W adapter (right)
Drawing more power also has another unfortunate side effect: the bottom of the chassis gets even hotter than before. I took some crude temperature measurements when I did the 2010 MacBook Pro reviews last year. I pointed an IR thermometer at the center of the bottom of the notebook, right where you'd have your lap, and measured surface temperature in a couple of scenarios.
While browsing the web with tons of windows/tabs open I noticed a small but tangible increase in surface temperature of the 2011 15-inch MBP compared to the 2010 model. Even the new 13 is warmer than last year's 15. Under light workloads none of these temperatures are high enough to really be a problem.
Load up the system however and you start getting into the uncomfortable zone. The new 15 breaks 38C, while the new 13 is actually only marginally warmer than the old 13 thanks to the use of Intel's HD Graphics 3000.
The biggest difference I noticed was the max temperature near the exhaust fan(s) on the notebooks. The new 15 is a whole 13C warmer than last year's model.
There's no way to get around it—if you're going to be using these systems to anywhere near their potential, they are going to get significantly warmer than last year's. Also, as a result, the new systems are noisier. Fans are more likely to spin up and given how small they are, they are quite audible. If this is a deal breaker for you, the best advice I can give you is to wait for Ivy Bridge.
Ivy Bridge will bring mild updates to the Sandy Bridge architecture, an increase in performance but more importantly it'll bring Intel's 22nm process. At 22nm I'd expect somewhat lower power usage than what we're seeing here today. Ivy Bridge is expected to ship in the first half of 2012, with updated MacBook Pros arriving ~2 months post introduction.
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Pandamonium - Thursday, March 10, 2011 - linkI own a 15" 2010 MBP and like the author(s) of "The Big Picture" section, I like using separate peripherals at home. I don't want to come off like I'm giving a sales pitch, but after a long wait, I bought a Henge Dock for my MBP. It's a $70 plastic mold whose only purpose is to hold your cables in place so you can easily/quickly "dock" a MBP.
For security concerns, I made an encrypted volume with OS X's disk utility and keep my frequently accessed sensitive stuff there. Everything else sits on my NAS.
I control heat and noise with SMC Fan Control. I've got a profile to keep "docked" fan speeds just a notch faster than default (the fan speed ramping up and down irritates me more than the absolute noise of the fan), and another profile for "lap use" to keep the machine at a comfortable temperature.
I too think that Thunderbolt is a big step towards an Apple docking station, but for now, the Hengedock, a NAS, and SMC Fan Control give me a solution that while not as elegant, is 95% of the way there.
Pandamonium - Thursday, March 10, 2011 - linkI should add that I use a Synology DS 209. If I could do it all over again, I'd go with QNAP. See my comments on Ganesh's Synology review for my reasoning. Cliffnotes are that I believe that regular SMART tests (to detect bit rot) should be part of a NAS's software stack and Synology's PR begs to differ. I'd love for Anand to offer clear advice one way or the other.
dagamer34 - Thursday, March 10, 2011 - linkDoes high amounts of heat ever mess up the screen or affect the dissipation of heat? I'd get worried if I were running a render or playing a game that caused my MBP to hit higher than the 80C it does now and the laptop just shuts itself down because it's too hot.
dagamer34 - Thursday, March 10, 2011 - linkBased on this review and using a 17" MacBook Pro (2011), here's my advice:
13" MacBook Pro - the changes from the 2010->2011 are good if you do CPU tasks, but mediocre to lame for GPU tasks. If you want to game, I'd wait until Ivy Bridge with a better GPU. Hopefully, we'll also see something more radical with ditching the optical drive allowing for a larger battery and dedicated GPU, but we'll see how that turns out.
Base 15" MacBook Pro - very good if you have CPU driven tasks, and what I'd recommend for most people. The only offsetting thing I see is that the next step up has a CPU, GPU, and VRAM bump, which may be very enticing for gamers.
High-end 15" MacBook Pro - for gamers, with the most optimal CPU, GPU, and VRAM configuration there is while still being very portable.
17" MacBook Pro - you love high-resolution screens for your work but still need to be portable. Very ideal because of the ability to have a full 1080p picture on the screen untouched for editing websites and such. Also good for photoshop. Likely for people that feel having an additional monitor is too much work, or their second monitor should be comparable in screen resolution to their main one.
I do hope the 2012 MacBook Pros cut away a lot of the fat: optical drive, FireWire port, USB port, ExpressCard slot and just have most of that functionality replicated with ThunderBolt. I feel like they could have gotten away with it this time, but there were no peripheral style docks ready, which is rather disappointing.
Ushio01 - Thursday, March 10, 2011 - linkOptical drives are still essential for those of us in the majority of the world who's internet is useless not to mention you never know if throttling or low data caps will be introduced in area's with currently good internet access subsequently making the loss of an optical drive a drawback.
Also interesting phrase cutting the fat or in other word's continue paying for a premium product but get even less for your money, yay.
dagamer34 - Thursday, March 10, 2011 - linkThat's what the $79 External SuperDrive is for.
Ushio01 - Thursday, March 10, 2011 - linkYay pay $1200+ for a laptop then pay $80 for the ability to use anything on it.
khimera2000 - Friday, March 11, 2011 - linkIts apple your paying out of the @$$ any how. If you where going for a budget, or "price VS performance" you would not be considering an apple. I think people looking at these will have 80 bucks to spare... at least be able to scrounge up 80 bucks when the need arives.
mianmian - Thursday, March 10, 2011 - linkYeh. Apple should have the upgrade option to replace optic drive to
1. a 2.5" drive slot
2. an extened battery.
gstrickler - Thursday, March 10, 2011 - linkI doubt you'll see either from Apple, however:
For #1, an OptiBay from MCE (MCEtech.com), or a DataDoubler from OWC (macsales.com). The MCE offers an external USB case for the removed SuperDrive so you still have the use of the SuperDrive, and it's USB powered so it's still portable.
For #2, HyperMac (hypershop.com) sells external portable batteries for the MB/MBP.