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zirition

macrumors newbie
Jun 23, 2013
6
0
When you said, "For me, it seems that i7 uses the full 15Watt, but i5 don't,at least for the most part of the time"

Or you saying your i7 uses the full 15w, almost all the time? like even web browsing / light work?

I was commenting the results of leslie11.

My 13/i7/8g/256g will arrive in Monday, it will be a long weekend...
 

DoctorK4

macrumors regular
Jan 31, 2011
142
3
If you are getting 15w on light stuff, there is something wrong with your i7.

I think the test was just an 8 minute Handbrake encode on the i7 (which took 10 minutes on the i5), which is an extremely processor-dependent task and essentially simulates the different effect of running each machine at pretty close to full CPU. I'm not sure what can really be concluded beyond the obvious that when ramped up near or at 100% the i7 will work harder than the i5, generating more heat, but will finish faster.
 

Jazwire

macrumors 6502a
Original poster
Jun 20, 2009
900
118
127.0.0.1
I think the test was just an 8 minute Handbrake encode on the i7 (which took 10 minutes on the i5), which is an extremely processor-dependent task and essentially simulates the different effect of running each machine at pretty close to full CPU. I'm not sure what can really be concluded beyond the obvious that when ramped up near or at 100% the i7 will work harder than the i5, generating more heat, but will finish faster.

I was just unclear when the OP said "most of the time", meaning "most of the time" as in always" or "most of the time" during the test.


That was cleared up though.
 

mayuka

macrumors 6502a
Feb 15, 2009
609
66
If so your i7 is messed up, right now i have about 7 browser tabs open, my email,Skype, which I would consider very light and Coconut reports I am using 3.3 watts.

This sounds extremely unrealistic. Considering that the display and other components draw power too. coconutBattery is measuring all power including cpu, display, keyboard lighting, ... They are using the built-in measurement to OS X, which is calculating the wattage over the last 30 minutes from the last charge or so.
 

Jazwire

macrumors 6502a
Original poster
Jun 20, 2009
900
118
127.0.0.1
This sounds extremely unrealistic. Considering that the display and other components draw power too. coconutBattery is measuring all power including cpu, display, keyboard lighting, ... They are using the built-in measurement to OS X, which is calculating the wattage over the last 30 minutes from the last charge or so.

Screenshot of coconut battery next to your post.
https://www.dropbox.com/s/fzoy0o91x18qgbi/screenshot.png
(Actually it was at 2.9 watts at the time when i took the screen shot.)
 

Mr. Retrofire

macrumors 603
Mar 2, 2010
5,064
518
www.emiliana.cl/en

bp1000

macrumors 65816
Jul 7, 2011
1,476
185
I know people are eager to see comparisons between each CPU option, myself included...

But from what I've seen so far with peoples tests the i7 is simply 20% faster as the paper figures suggest only when performing tasks that max out both cores eg video encoding.

The i7 draws more power and therefore runs hotter during these tasks. I think idle temps would be very similar.

I think the difference in normal usage battery life is also similar.

Anandtech review of the i7 will be interesting but I expect it to show more of the same.

In a nutshell 99% of the time the i7 gives no advantage runs perhaps 1-2c hotter, draws less than 5% more power but will compute slightly quickly when doing really heavy duty stuff.

As this is a portable thoroughbred I believe the i5 is the best bet.

Do a lot of video or graphics work, the rMBP quad i7 is your best bet. Or iMac plus MBA is unbeatable.
 

Scott6666

macrumors 65816
Feb 2, 2008
1,487
936
I just ran a simple Handbrake encode on both machines, side by side with nothing running in the background except Coconut battery.

Here are a few observations:
- a 10min encode on the I5 took 8min on the I7
- the I7 fan spun up to 6.5k rpm within 2min, the I5 kept at 1.2k rpm till the 5min mark then slowly increased to 1.6k rpm by the end of the test
- Coconut batt consistently showed the draw for the I7 at 22.5w and the I5 at 14.5w

Guess the I7 is going back to Apple then.

GREAT Test. Real data. Explains what's really happening rather than trying to guess by circumstantial evidence!

I'm persuaded to get the i5 (hate fans). I want the 8GB/512GB model and was hoping to have instant store pickup and was trying to avoid the BTO route. That was pushing me toward the i7. But now I have direction. Thanks.
 

leslie11

macrumors newbie
Jun 21, 2013
15
0
No prob folks, glad that my simple test helped some of you with your decision.

I must stress that my main aim was to see the extent of heat generation, batt life and performance are secondary, so please factor that in.

Your usage pattern might be different from mine, I'm on my MBA for hours at a stretch but I'm usually plugged in and don't run CPU intensive tasks, mostly word processing n surfing. In this case, both machines performed about the same, performance and heat-wise.

----------

I forgot to add, I really didn't want to buy both machines at first but the I7 which I first ordered was running kinda hot so I decided to get the I5 and then return the one I felt was better for me.

I really didn't want to waste Apple's money for the shipping, restocking etc. and by posting here in MR, I guess I'm trying to make up for the extra unit I ordered.
 

Scott6666

macrumors 65816
Feb 2, 2008
1,487
936
Why is it that iStat does not show CPU temps in people's tests? Just things like enclosure or memory temp.

IStat on my 2011 shows both the CPU and the CPU heat sink? No sensor for Haswell CPU or does iStat need to be updated to read the CPU?
 

solmaker

macrumors member
Nov 23, 2007
89
14
>>a 10min encode on the I5 took 8min on the I7
>...from what I've seen so far with peoples tests the i7 is simply 20% faster
>as the paper figures suggest only when performing tasks that max out both
>cores eg video encoding.

Actually that's 25% faster (not 20% faster) from this test:
i5 speed = 1/10 video/minute
i7 speed = 1/8 video/minute
i7/i5 speed = (1/8)/(1/10)=10/8=1.25=125% (so 25% faster)
 

entatlrg

macrumors 68040
Mar 2, 2009
3,385
6
Waterloo & Georgian Bay, Canada
Fair to say the i5 runs a little quieter and cooler with 5 to 15% better battery life depending on what tasks you're doing and 25% slower when maxing out both cores?

That sums up my experience. Since the i5 is quiter and cooler doing everyday type tasks where the i7 isn't noticeably faster and I think I'm able to get 30-60 minutes more on the battery the i5 was my choice.
 

sofianito

macrumors 65816
Jan 14, 2011
1,207
2
Spain
Thanks Jazwire. Really useful and interesting tests.

Just a couple of suggestions:) : There are tools that allow you to monitor and measure more precisely CPU temperature and fans RPM.

It would be also nice if could do the tests on Mavericks DP2.
 

Ifti

macrumors 68040
Dec 14, 2010
3,922
2,432
UK
That sums up my experience. Since the i5 is quiter and cooler doing everyday type tasks where the i7 isn't noticeably faster and I think I'm able to get 30-60 minutes more on the battery the i5 was my choice.

No. During everyday tasks where both i5 or i7 arent really pushed very much, the power draw is around the same, hence battery life will only differ by minutes. The reviews of the 13" model prove this.

You will only notice a larger battery life difference when pushing both CPUs to their turbo boost levels, where the i7 will finish the task sooner, but will draw more power then the i5.
 

Porkaysi

macrumors member
Sep 17, 2012
40
6
I know this mite not be the most exact comparison. I5 is definetly cooler and has no fan noise that I herd while I had it for 2 weeks. The I7 on the other hand has a very slight fan noise that I can hear, and it does get warm. I have 2 fans in my room and sometimes I second guess it's my air making the noise it is that faint, and the warmth is far from hot but my I5 never ever felt warm while I had it.
 

osofast240sx

macrumors 68030
Mar 25, 2011
2,539
16
I'm going to pull the trigger on a MBA i5, 8g, 512, apple care, MS office 2011 home/business. This Is for the wife. I don't want to risk lower battery life with the i7. Buying from macmall to avoid the $189 in tax.
 

entatlrg

macrumors 68040
Mar 2, 2009
3,385
6
Waterloo & Georgian Bay, Canada
I know this mite not be the most exact comparison. I5 is definetly cooler and has no fan noise that I herd while I had it for 2 weeks. The I7 on the other hand has a very slight fan noise that I can hear, and it does get warm. I have 2 fans in my room and sometimes I second guess it's my air making the noise it is that faint, and the warmth is far from hot but my I5 never ever felt warm while I had it.

Why did you change from the i5 to the i7?
 

Porkaysi

macrumors member
Sep 17, 2012
40
6
Why did you change from the i5 to the i7?

I wanted the I7 but I had a huge bb gift card and an old gaming desktop/ heavy duty tasks. Used the gift card got the I5 sold it and my desktop. I consolidated to an ultimate air that's the only reason really.
 

Saturn1217

macrumors 65816
Apr 28, 2008
1,271
847
I wanted the I7 but I had a huge bb gift card and an old gaming desktop/ heavy duty tasks. Used the gift card got the I5 sold it and my desktop. I consolidated to an ultimate air that's the only reason really.

Do you notice a difference in performance between the two? Would you recommend the i7 to others who usually do basic tasks but occasionally do more demanding tasks? Thanks for your input!
 

Porkaysi

macrumors member
Sep 17, 2012
40
6
Do you notice a difference in performance between the two? Would you recommend the i7 to others who usually do basic tasks but occasionally do more demanding tasks? Thanks for your input!

Honestly I never did anything to crazy with my I5, one thing I can test is making a hierarchy chart on word. That made my I5 lag 2 seconds a key stroke, so when I get home il try the same thing again.battery wise they are similar I have not noticed any difference. The I7 is warmer then the I5 on the top by the hinge but the I7 does not even get that warm after 2 games of LoL running bootcamp.
 

willgreene99

macrumors regular
Dec 16, 2010
217
16
DFW
Really appreciate your time on this Jazwire. I know you may have more important things to do, like earn a living, but your efforts on this endeavor do help me in deciding the version I want to get.
 
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