Beware: the Core i7 is probably not worth it this time

Nuak

macrumors member
Original poster
Oct 29, 2009
38
0
Before purchasing, you should know that besides the CPU speed there is only 1 difference in terms of architecture between the Arrandale i5s and the i7: the i7 includes 4MB of L3 cache while the i5s include 3MB of L3 cache. Nothing else. You compare the three of them in Intel's website: http://ark.intel.com/Compare.aspx?ids=43560,43544,47341

Check this article:
http://www.notebookcheck.net/Review-Intel-Core-i3-i5-i7-Processors-Arrandale.25085.0.html

Look at this picture. The first three are the ones included in the different 15" configurations. They are quite similar in performance:


This one is about gaming performance with the integrated GPU included in all Arrandales. Suprisingly, the i5s perform better. Check the article to know why.


Now look at this one. It shows the power consumption. The consumption of the i7 is significantly higher. That means less battery life and more heat.


Given that the increase of VRAM in the higher model has little impact in performance, I recommend you to think before you buy. I would go for the i5-520M 2.4GHz. Most of us couldn't tell the difference between the three CPUs. Keep in mind that the i7 name is just marketing, because the i5s and the i7 are all the same CPU with the only difference of 1MB L3 cache.
 

vasuba

macrumors member
Apr 13, 2010
85
0
You are correct. Besides the obvious video ram differences in the models the performance boost of the i7 versus the i5 is only about 5% so extremely negligible.

So if you are not going for the 512mb GPU pretty much best to just stick to the i5
 

M1K3YY

macrumors newbie
Mar 18, 2010
24
0
interesting info...iwas leaning towards the i7..but after seeing this i might stick with the i5
 

jonesjb

macrumors member
Dec 20, 2009
35
0
Now look at this one. It shows the power comsumtion. The comsumtion of the i7 is significantly higher. That means less battery life and more heat.
But doesn't the i7 have a larger battery to compensate?
 

Quicksilver867

macrumors regular
Jun 25, 2007
186
20
Columbus
I'm fairly certain the 8-9 hour range specified by Apple is because of the i5/i7 discrepancy. i5s will be closer to 9, and i7s will be closer to 8.
 

D0rk

macrumors member
May 23, 2009
56
0
Those charts really make me wish they offered the mid-range i5 with the 512mb of video RAM as an option at least.
 

vasuba

macrumors member
Apr 13, 2010
85
0
Those charts really make me wish they offered the mid-range i5 with the 512mb of video RAM as an option at least.
Totally agree with you. Im being stuck buying the i7 15" simply because I have to have the 512mb video ram.
 

waloshin

macrumors 68040
Oct 9, 2008
3,169
66
Well that's interesting I wonder why Apple didn't choose to use a Quad Core for the 17" was it because Ghz sell not cores?
 

FMD:.

macrumors member
Feb 16, 2010
37
0
If you look closely the i7 was beat in 2 of the 3 3D tests. So you cannot say that it was the best in every test. Best overall...probably...but that can be debated with the amount of power consumption/heat etc.

As well as 2 of the pc benchmark tests (memories and hdd tests) and was extremely close with movies and music.
 

raykhrud

macrumors regular
If you look closely the i7 was beat in 2 of the 3 3D tests. So you cannot say that it was the best in every test. Best overall...probably...but that can be debated with the amount of power consumption/heat etc.
If you ever bothered to read the original article where the images come from, it clearly says that the reason for the i7's failure to be the first in those tests is GMA HD not getting enough power. As you might know, both i7 CPU and GMA HD GPU are located on the same chip (glued together) and have one power source. As you most likely will never use (because you won't really be able to do that) GMA HD for any graphics-heavy tasks, i7 will always be the fastest Arrandale CPU for you.
 

joina

macrumors member
Oct 24, 2009
56
0
Bath,uk
thank you very much. would you mind to find some benchmark for C2D 3.06 as well? that is the best cpu we can get in last MBP
 

C64

macrumors 65816
Sep 3, 2008
1,228
219
Wow, didn't know that the difference between the i5-520M 2.4GHz and i5-540M 2.53GHz was so small... like.. almost nothing for real life applications.

And the only other difference is the 320GB vs 500GB hard drive. I was thinking about the mid range 15", but now...
 

FMD:.

macrumors member
Feb 16, 2010
37
0
Yeah but it doesn't state that it is the best chip. Its the fastest by supposedly single digit percentages. That to me does not seem much faster and I am sure most people will not be able to tell if thier program opens up a half a second faster. They probably will be indistinguishable when ran side by side.
 

C64

macrumors 65816
Sep 3, 2008
1,228
219
If you'll be needing that extra VRAM, go for the i7.

But I don't see a reason anymore to otherwise go for the 2.53GHz over the 2.4GHz — apart from being able to say that you have the 2.53GHz model ;) Use the difference in price to bump the resolution of the screen.

In real life you'll never notice it. It'll be a 60 sec difference on a 60 minute render, or something like that. And if you really want your day-to-day apps to feel faster, swap the HD for an SSD.
 

aneftp

macrumors 601
Jul 28, 2007
4,247
463
Well that's interesting I wonder why Apple didn't choose to use a Quad Core for the 17" was it because Ghz sell not cores?
Quad Core i7 mobile chips (720qm) were horrible on laptop battery life when released on windows pc. People were lucky to get just 2 hours of battery life. Great performance. Horrible battery life.

That's why Apple said no to the the quad core i7s.
 

Nuak

macrumors member
Original poster
Oct 29, 2009
38
0
If you'll be needing that extra VRAM, go for the i7.

But I don't see a reason anymore to otherwise go for the 2.53GHz over the 2.4GHz — apart from being able to say that you have the 2.53GHz model ;) Use the difference in price to bump the resolution of the screen.

In real life you'll never notice it. It'll be a 60 sec difference on a 60 minute render, or something like that. And if you really want your day-to-day apps to feel faster, swap the HD for an SSD.
That's the point. For a noticeable performance gain it's better to spend money on a 2.4 + SSD rather than the 2.53 or the 2.66.