The iPad 2,4 Review: 32nm Brings Better Battery Life
by Anand Lal Shimpi on May 4, 2012 12:50 AM ESTSignificant Battery Life Improvements
We'll start with the latest iteration of our WiFi web browsing test. With some additional logic to defeat overly aggressive browser caching, this test cycles through dozens of web pages, pausing on each one to simulate reading time before moving onto the next one. Display brightness is kept constant at 200 nits while the test runs. Results are reported in hours of battery life before the tablet dies.
Most web browsing tests end up being significantly display limited, as in the display dominates most of the power draw. That being the case, the fact that we see a 15.8% increase in battery life from the new 32nm HK+MG SoC alone is very significant. Apple is very conservative internally about revising battery life ratings so it's no surprise that we don't see a change in the specs on the iPad 2, especially considering that so many units out there on the market are still older iPad 2,1 models.
The increase in battery life here is almost certainly due to lower leakage at idle and better active power as well. This is a real improvement.
Things get even better when we stress the real power hog on the SoC: Imagination Technologies' PowerVR SGX 543MP2 GPU. Taking up more area on the die than the dual Cortex A9 cores, the 543MP2 is really stressed during 3D gaming. What better way to measure the impact of the new 32nm SoC on battery life than with one of the most stressful 3D games out for iOS today: Infinity Blade 2.
Here we're looping through the same scene until the battery dies, once again at normalized brightness.
The 3rd generation iPad obviously doesn't do as well as the iPad 2 here, as it not only has a more power hungry GPU but it's also rendering the scene at a higher resolution (and driving a higher resolution panel). What's most impressive however is just how much better the iPad 2,4 does here: a 29% increase in battery life over the original iPad 2,1.
Riptide GP, a less stressful title, shows us similar results:
Finally we have our brand new video playback test. Here we've got a copy of the last Harry Potter movie with the credits stripped out (1:58:00 running time), transcoded to a 720p High Profile H.264 video with a 4Mbps average bit rate, playing back in a loop until the battery dies.
The iPad 2 holds a 19% advantage over the 3rd generation iPad (once again for obvious reasons), however the iPad 2,4 absolutely dominates with an 18% increase in battery life. At 15.7 hours this is an insane amount of battery life from a single charge. Granted end users will see lower numbers if you watch at higher brightness settings (200 nits on our test panel was around 40% brightness), but the advantage from the new iPad should still remain just as significant.
Facebook
Twitter
RSS
100 Comments
View All Comments
LittleMaNiaC - Monday, June 11, 2012 - link
HI guys! I would like to ask you all. Those who bought ipad 2,4 are from U.S right? I wonder did any of those ipad 2,4 went to Asia?machugger - Wednesday, June 27, 2012 - link
Why would an iPad 2 w/serial no. starting w/"DM" that was manufactured1) in the same factory as the 2,4
AND
2) AFTER April, when the 2,4 models were made
…why would it be a 2,1?!?!?!?!?
marketjock - Monday, July 30, 2012 - link
From Apple's website, when adding the iPad 2 16GB to your cart, the part number MC954LL/A is used. Is it safe to say when looking for a new one, to only look for MC954LL/A as that will have the 32nm chip?marketjock - Monday, July 30, 2012 - link
From what I have read, it does not matter the part number or the S/N. Any can have the 45nm or 32nm chip. It appears to be a matter of exhausting out the 45nm inventory.TechKnow12 - Wednesday, August 1, 2012 - link
Hi,If anyone is after the iPad 2,4 please read the following.
If you're in the US, look for:
MC769LL/A, 16gb, Black - Serial prefixes: DMQH, DMPH - both proven to be 2,4
MC979LL/A, 16gb, White - Serial prefixes: DMQH, DMPH
MC954LL/A, 16gb, Black - new model number, serial prefix not known - proven to be 2,4
MC989LL/A, 16gb, White - unproven but as it's the new model number it should be 2,4
If you're in Australia, look for:
MC769X/A, 16gb, Black, Serial prefixes: DMQJ, DMPJ - proven to be 2,4 by me.
MC979X/A, 16gb, White, Serial prefixes: DMQJ, DMPJ
The MC954 & MC989 appear to be US only models.
Please note that the Australian models may possibly have the prefix with H at the end instead of J and vice versa for US.
If you live in Australia I can confirm that the Apple Store in Perth has the DMQJ & DMPJ in stock. I purchased mine from Big W however I had to check with 4 stores before I found a DMPJ.
Battery Life
Okay so now you're wondering if the alleged extended battery life of 11.7 hours makes this worth buying or not.
Well, out of the box my iPad 2,4 had a charge of 76% and for the next 2 hours, from setting up, to installing my Apps, to surfing the net the charge only dropped to 66%. Wow! Then I discovered that Bluetooth was switched on by default the entire time which would have no doubt added to the battery drain, thus I managed 10% battery usage in 2 hours using wifi and with Bluetooth on. Double wow! It has now been 7 hours since I first powered the iPad on and I'm only down to 43%. Bluetooth was turned off when I found it was on, of course. In that 7 hours the iPad wasn't in use for about 30 minutes (had to have a couple of breaks) so actual usage would be 6.5 hours.
So depending on how you use the iPad I'm thinking you may get a minimum of 11.7 hours general usage (therefore non gaming or video watching) and possibly a maximum of 20 hours general usage.
Lastly, if at some point down the track you decide to sell the iPad 2,4 (like when the iPad 4 with the Sharp IGZO screen gets released) I'm sure you'll be able to sell it on eBay for a good price.
Saint04 - Wednesday, August 1, 2012 - link
I can confirm your findings with the white iPad 2,4. I picked one up from Walmart today with a production year of 2012 in the month of June. The part # is MC979LL/A. However my serial prefix doesn't match your findings. My serial prefix is DYTH. I could have used your findings the day before yesteday. I went through four of these before getting ahold of an iPad 2,4. So far it runs great and I'm relieved to get ahold of one. I'll be selling my new iPad on ebay as the quicker charging time and battery life on the ipad 2 is more important to me at the momment. I use my iPad in classes (all day sometimes) to take notes, read course books and I don't always have access to an outlet. I'll be looking forward to the Gen 4 iPad and the iPad 2,4 will suffice for now.TechKnow12 - Thursday, August 2, 2012 - link
That's awesome Saint04. Glad to hear you found one! I know the feeling of being "relieved" at finding the 2,4. I set myself up to be disappointed when I purchased mine (expected only to have a 2,1) but then of course I was over the moon when Linpack revealed it was a 2,4. :DThanks very much for letting us know about the DYTH serial number prefix too! I'll pass on this valuable bit of info at other forums.
No doubt as the old stock of iPad 2's gets sold off it will become much easier to find the 2,4 and there will be a plethora of serial numbers to look out for.
Enjoy your 2,4 Saint04! And if you revisit this site, please let us know roughly what battery life you're getting. Thanks! :)
Saint04 - Monday, September 10, 2012 - link
Hey TechKnow12. The battery life was close to advertised in performance as what anandtech reported in the ipad 2, 4 article. I apologize for the late response, I didn't realize that I had one until I was reading back over the forum. Also, just purchased another ipad 2 with the MC979LL/A part number it too was the new ipad 2,4. Take care, grace and peace.boofarino - Saturday, August 18, 2012 - link
hi i just wanted to confirm that the serial code DMPH is accurate. I went to micro center in minneapolis and bought an ipad with serial DR, and it was an ipad 2,1. I returned it and purchased one from best buy in richfield. At first he also said they only had ones with the DR serial number but after asking him to check again he came back with a DMPH, the protective plastic was a bit ripped and dirty so maybe it was older stock, but on coming home and powering it on i was very happy to see that it was an ipad 2,4. thanks for all the help guys, especially Technow 12. very happy to have the one with extra battery life. And also when i was in the best buy store I was suprised to realise that there is a significant difference in weight when holding the ipad 2, and ipad 3, i know its meant to be imperceptible but the ipad 2 definitely feels lighter.Arpajon - Monday, October 22, 2012 - link
I've checked a couple of local stores this week and can find neither an MC769LL/MC979LL DMQH/DMPH nor an MC954LL/MC989LL. Has anyone in the States had any recent success in finding a 2,4?One other question... I've never owned an Apple iAnything - if the iPad Mini comes out tomorrow as rumored, is the iPad 2,X likely to be discounted immediately?