Notebook config question: dual or quad core CPU  

In the panorama field, hardware is also part of the success. You can discuss here about it: camera, computer, pano head, anything
no avatar
RPMcCormick
Member
 
Topic author
Posts: 16
Likes: 0 post
Liked in: 0 post
Joined: Sun Aug 29, 2010 3:34 pm
Info

Notebook config question: dual or quad core CPU

by RPMcCormick » Sat Dec 11, 2010 4:19 pm

Going to be purchasing a new DELL Latitude E6510 notebook ... and have a choice between these two CPU configurations which are really no different in cost:

Intel Core i7-740QM Quad Core 1.75 GHz 6MB cache
- or -
Intel Core i7-640M 2.8 GHz 4MB cache turbo boost

Operating system will be 64-bit Windows 7 with 8 GB of 1333 MHz memory and a 7200 RPM disk.

Based on Autopano Giga today and the version being developed ... which of those are the better CPU choice?

My gut feeling: unless a lot of the Autopano code is designed to make use of four cores (at 1.75 GHz) I would probably be better off having two cores that can run over 30% faster per core. (My logic being something that is single threaded is going to get done a lot faster at 2.8 GHz than 1.75 GHz.)

Appreciate any feedback and direction.

With best wishes for the holidays ...

- Bob McCormick

no avatar
foundation
Member
 
Posts: 276
Likes: 3 posts
Liked in: 2 posts
Joined: Mon Jan 15, 2007 4:43 am
Info

by foundation » Sat Dec 11, 2010 10:42 pm

you actually need to compare the turbo boost frequences. As the intel chips can overclock themselves when single threaded apps are detected (it shuts down the other cores temporarily to have the heat/electrical budget to overclock).

The 740qm can run one core at 2.93 GHz according to intel's web site http://ark.intel.com/Product.aspx?id=49024

and the 640m can turbo boost to 3.46 GHz according to http://ark.intel.com/Product.aspx?id=49666&code=640m

which is a much smaller delta. There are definitely quite a few of autopanos internal steps that are well multi threaded as well. Another difference to look at is the power consumption. The quad core has a max power of 45w vs. 35w for the dual core, so you'll get better battery life from the dual core

no avatar
foundation
Member
 
Posts: 276
Likes: 3 posts
Liked in: 2 posts
Joined: Mon Jan 15, 2007 4:43 am
Info

by foundation » Sat Dec 11, 2010 10:43 pm

also if you shoot in raw, the writing out of the temporary TIFF files takes a fair amount of disk time, so a fast hard disk is advisable

no avatar
RPMcCormick
Member
 
Topic author
Posts: 16
Likes: 0 post
Liked in: 0 post
Joined: Sun Aug 29, 2010 3:34 pm
Info

by RPMcCormick » Sun Dec 12, 2010 8:17 pm

Code: Select all
              Cache  Clock Turbo Pwr  Max    Mem      Band
CPU      Core    MB    GHz   GHz   W  Mem  Speed     Width
i7-740QM    4     6   1.73  2.93  45  8GB   1333  21.0GB/s
i7-640M     2     4   2.80  3.46  35  8GB   1066  17.1GB/s

Thanks for the pointers to the Intel web pages for each. Both of these Intel CPU's have been recently launched. As for battery life I am probably not too concerned about that. I have spec'ed the 9-cell (largest) battery but I expect the majority of my use of such a system to be whilst it is connected to the AC mains.

What I didn't see in my first pass review of two similar configurations is noted above: the quad core CPU supports 1.333 GHz memory but the dual-core configuration only 1.066. (A bit misleading because I believe the configuration for the dual-core had the faster memory which led me to believe both systems had the same memory bus speed.)

A 7200 RPM disk is the fastest available excepting an SSD which at this point I don't plan on investing in. (My home system is dual Xeon 5130 CPU with 8 GB memory and 15k RPM SAS drives.)

I guess now I lean a bit towards the quad core based configuration ...
Last edited by RPMcCormick on Sun Dec 12, 2010 8:19 pm, edited 1 time in total.

no avatar
tived
Member
 
Posts: 796
Likes: 0 post
Liked in: 0 post
Joined: Fri Jul 11, 2008 3:49 pm
Location: Dane in Western Australia
Info

by tived » Mon Dec 13, 2010 1:26 am

I think that you will gain more on the faster CPU at the moment (next 2 years) over the more cores, simply because most of the software still can't fully take advantage of the more cores. ( I am saying this despite having just build a 2x Hex core Intel, but I choose that over the 2x 12core AMD, simply because i think for what we do in digital photography, we need high speed first, then lots of memory, but most importantly fast HDD's and if you can get more cores then that comes down the priority list.
You money is best spend on the SSD drive! anything else is a waste of money! The SSD will make up for the slower processsor! IMHO! in real life.

If you replaced your 15k drives, with a couple of Green disks at 5400rpm, you would think your system was running in slow motion, the same is the case when you go to SSD, but the otherway around, though you could consider the WD raptor 600GB 2.5" 10000rpm drive for your laptop.
a
if I find the time next year i will run some test between the effect of SSD's over HDDs when doing pano's and other photo related tasks

good luck

henrik

no avatar
RPMcCormick
Member
 
Topic author
Posts: 16
Likes: 0 post
Liked in: 0 post
Joined: Sun Aug 29, 2010 3:34 pm
Info

by RPMcCormick » Mon Dec 13, 2010 1:40 am

Thanks Henrik for your comments and suggestions!

So I tend to agree - I was leaning toward selecting the dual core processor with the faster execution performance until I noticed that the quad core system has aprox 20% faster memory bus speed - which I will assume will help greatly in pushing things around in ... memory.

The notebook I currently have only is 3GB RAM and 32-bit Windows 7. Also a horrible video sub-system. It is pretty useless running Autopano. I would like to be able to run Autopano Giga on a notebook especially when I am traveling - but not necessarily as my primary system.

I may consider some SSD devices for one of my home systems in 2011 ... right now I don't do enough work (purely amateur) to justify the cost - and I'm pretty happy with the performance I have now (with the 15k RPM disks).

Happy holidays ...

no avatar
hankkarl
Member
 
Posts: 1284
Likes: 0 post
Liked in: 0 post
Joined: Tue Feb 21, 2006 5:32 pm
Location: Connecticut, USA
Info

by hankkarl » Mon Dec 13, 2010 7:07 am

The E6510 is a 15" laptop. I got a Studio XPS 17 because I can stick two hard drives in it. The Alienware 17 also can take two hard drives. The Latitude only has a 16" model, but it takes two SSDs and costs a bundle.

But the Studio 17 is a big machine-when I fly, I take a 10" netbook.

BTW, watch the overclocking spec. You only get the max when you run one core. When all cores are running, you may have to de-rate them.

If you look at http://en.wikipedia.org/wiki/List_of_Intel_Core_i7_microprocessors, you'll see a number for "turbo" like 1/1/6/9 for the 740QM. Turbo describes the available frequency bins (+133 MHz) of Intel Turbo Boost Technology that are available for 4, 3, 2, 1 active cores respectively. The 640M turbo numbers are 3/5, and the frequency bins are 133MHz also.

Note that overheating and certain power saving modes may reduce the processor speed dramatically.
Last edited by hankkarl on Mon Dec 13, 2010 7:16 am, edited 1 time in total.

User avatar
[bo]
Member
 
Posts: 1226
Likes: 0 post
Liked in: 0 post
Joined: Fri May 05, 2006 8:16 am
Location: Bulgaria
Info

by [bo] » Mon Dec 13, 2010 1:01 pm

I'd take more cores to higher GHz any day, when it comes down to working with Autopano! It's great in utilizing the multiple cores, especially in detection and rendering!
Some of my panoramas, posted in the Autopano Pro flickr group.


Who is online

Users browsing this forum: No registered users and 3 guests