Own both i5 and i7 2012 13" now

ronswanson

macrumors newbie
Original poster
Sep 30, 2012
20
0
My wife has a i5 4GB 128 GB model now and I have an i7/8GB/256GB MBA - both from mid -2012 - bought off the refurb store.

We are both happy with the performance - both machines are blazingly fast with no lag whatsoever. I bought the i7 because I am a scientist and also like to have every program on the computer open.

Wanted to summarize my experience so far for others. The i7 can handle having everything I have open easily - I run scientific computation programs like MATLAB and python but also have safari, chrome and every icloud application running now. Also, Papers2. I think the i5 can handle most of this too, perhaps with some minor trouble due to memory.. but I prefer my i7.

Both machines are always reasonably cool to the touch under any load. Under max load, they are definitely warm in parts but would be comfortable even on your bare genitalia if you are the kind who does that.

Battery life seems decent on both though we need more time to decide on that - > 6 - 7 hours for now.

The main problem with the i7:
1. Sudden rapid climbs of core temperature to 100 C when I throw a difficult task at it - followed by equally rapid drops within 2 seconds to 50 C at the end of the task. It's not so bad if you let the fan run at say 4000 RPM.. not dead quiet like it is under 3500 but still pretty quiet.

2. More annoying, it sometimes idles at 70 - 80 C when I am only downloading a large file and browsing at the same time. The CPU usage is less than 30% and yet it'll be at 80 C sometimes.. dont see a pattern yet but it has been happening.

Under normal use though - like right now where a 100 programs are idling and I am typing this in Safari - it idles at 45 - 50 C for me.

All in all, I am happy with having chosen the i7 so far. What would make me change my mind is if (2) above keeps happening during normal use and if (1) happens every time I try taxing it. The CPU apparently throttles above 100 C, slowing down the machine..

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Does anyone know of good programs to monitor , control and record fan speed and temperature on a mac?
I am using SMCFanControl and iStat widget right now but neither will keep a log of the stats..
 

blesscheese

macrumors 6502a
Apr 3, 2010
695
175
Central CA
But how does it do running Skyrim, or any other recent high-spec game?

I'm actually serious...I use some intense programs, kinda like you do, on my 2009 Air, and it can run them all without a hitch, brief climbs in temp & processor usage, and then back to normal when it is done with the computation.

But, when (in Bootcamp, admittedly) I run Skyrim on it, the temps climb, and the processors run hotter and hotter...but, it still runs it! I'm sure the newer models would do better; I'm hoping the 2013 model Air makes it worth my while to upgrade.
 

tiwizard

macrumors regular
Jul 12, 2010
233
0
But how does it do running Skyrim, or any other recent high-spec game?

I'm actually serious...I use some intense programs, kinda like you do, on my 2009 Air, and it can run them all without a hitch, brief climbs in temp & processor usage, and then back to normal when it is done with the computation.

But, when (in Bootcamp, admittedly) I run Skyrim on it, the temps climb, and the processors run hotter and hotter...but, it still runs it! I'm sure the newer models would do better; I'm hoping the 2013 model Air makes it worth my while to upgrade.
For games, you'll definitely want to wait for the Haswell architecture. The graphics performance is much improved from Ivy Bridge.
 

sviato

macrumors 68020
Oct 27, 2010
2,282
45
HR 9038 A
Both machines are always reasonably cool to the touch under any load. Under max load, they are definitely warm in parts but would be comfortable even on your bare genitalia if you are the kind who does that.
Hope you and your wife don't plan on having any more kids if you constantly use your laptop on your lap ;)
 

ronswanson

macrumors newbie
Original poster
Sep 30, 2012
20
0
Heh.. the genitalia thing was a joke. Guess that didn't come through. Strangely enough, we are expecting our first child any day now!

I do not use my Air on my lap. Either way, the Air does not have underside vents. Some of the rapid overheating happened even when I was holding the Air up in bed.. anyway, in the course of the day, I've found that my i7 air has been much cooler in regular use (no heavy scientific computation though.) Perhaps there is one program on my computer which causes overheating.

Does anyone know a proactive fan speed adjusting program for the MBA? SMC Fan Control doesnt cut it - I need to manually bump up the rpm. I want an automatic rpm adjuster, like what Apple has built-in, only more aggressive.
 

Skoopman

macrumors 6502
Sep 24, 2011
318
2
2. More annoying, it sometimes idles at 70 - 80 C when I am only downloading a large file and browsing at the same time. The CPU usage is less than 30% and yet it'll be at 80 C sometimes.. dont see a pattern yet but it has been happening.
The faster you download, the more the CPU heats up, it's pretty normal. I have a 120 Mbit/s line here and it does reach 80-85 °C when I download at full speed.
 

Jobsian

macrumors 6502a
Jul 30, 2009
828
13
As you suggest, I'm guessing the memory difference likely accounts for the bulk if not all of the differences you notice. If you think about it, the CPU bottleneck won't be noticed unless the i5 was at 100%.

I have an i7. If I had known about the benchmarks before I bought my 2012 (better battery in i5 and less idling heat), I would have certainly gone for i5. But they're both fine notebooks.
 

Mac32

Suspended
Nov 20, 2010
1,263
452
My 2010 1.6ghz C2D MBA 11' idles at 36-38 celsius, also using CoolBookController (which doesn't make a huge difference, but is noticable). When I watch hi-res flash videos or something else demanding it'll get up to around 60c, maybe 62-64c. The fans pretty much never speed up with my usage (Office, Internet, watching movies, iTunes, email, Skype etc.)
Wow, these machines have really become a lot hotter, too bad.
 
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