i5 or i7?

sgsdxzy · 03-01-2012, 04:23 PM #1

I am going to buy a new notebook for my university life. I just wonder which cpu is better for dolphin: i7 2670QM(2.2G-3.1G quad) or i5 2540M(2.6G-3.3G dual). Is quad core well-supported?

**admin89** · (This post was last modified: 03-01-2012, 05:20 PM by admin89.)

Quote:i5 or i7?

Depend on your purpose :
_More battery life : get the i5
Note that the i5 has lower TDP therefore it should produce less heat than i7

_Faster video encoding : get the i7 (although i5 2540m is faster than i7 740qm which is good enough)

_Dolphin benchmark : May be the same (i5 turbo to 3.1Ghz on 2 core mode, 3.3Ghz is single core mode ; i7 turbo to 2.9-3.0Ghz on 2 core mode , 3.1ghz is single core mode) . But due to higher base clock speed , the i5 is faster but the difference is not noticeable

Quote:Is quad core well-supported?

Nope

Edit : what's about the GPU ? Intel HD 3000 is out of the question

sgsdxzy · 03-01-2012, 05:32 PM #3

(03-01-2012, 05:18 PM)admin89 Wrote: Edit : what's about the GPU ? Intel HD 3000 is out of the question

It's gt550m or gt525m. I think it should be enough. I don't care much how games look.

So you say these two cpus may have similiar performance about dolphin. Considering I have other pc games and programs to run, and dolphin may one day support quad core, I prefer i7.
Dolphin has not yet supported quad core, so the openmp is useless at the moment? My ICC would be sad……
By the way, I use linux, so I only have OpenGL.

~~Duke Nukem~~ · 03-01-2012, 06:02 PM #4

(03-01-2012, 05:32 PM)sgsdxzy Wrote:
(03-01-2012, 05:18 PM)admin89 Wrote: Edit : what's about the GPU ? Intel HD 3000 is out of the question
It's gt550m or gt525m. I think it should be enough. I don't care much how games look.

So you say these two cpus may have similiar performance about dolphin. Considering I have other pc games and programs to run, and dolphin may one day support quad core, I prefer i7.
Dolphin has not yet supported quad core, so the openmp is useless at the moment? My ICC would be sad……
By the way, I use linux, so I only have OpenGL.

Please consider a dual boot with Windows 7 because you're going to find out that games will run more smoothly and fluently in Windows with DX9 as the video backend in Dolphin.

**admin89** · (This post was last modified: 03-01-2012, 06:40 PM by admin89.)

Quote:dolphin may one day support quad core

short answer: No!
long answer : Never
why ? Read NV post( post 3)

OpenMP has nothing to do with quad core support
You may gain 0-5 FPS if you enable that options (depend on the game)

Dolphin won't run well on the laptop unless that laptop has very good cooling design (Asus G series , MSI G series, Alienware) .
CPU will be underclocked if the CPU overheat . That's why i chose i5 480m over i7 740qm but it's just my opinion
Besides , i don't trust turbo boost because i saw so many threads like this....So the one with higher base clock ,run cooler ... is the winner

sgsdxzy · 03-01-2012, 06:46 PM #6

Aren't openMP supposed to use multiple threads? I thought it could imply multiple threads to do the same thing and these threads can run on multiple cores……
Cooling has something to do with your climate I suppose…… Imagine I am at the north pole……Just a joke. I have a notebook for 5 years, and I never care about its cooling. It's still fine.
I don't trust turbo too……But game is only a small part of my computer. I think my mathematics problems will happily welcome a quad core friend. Moreover, I am quite tolerant about games I like. The notebook mentioned above has T7300@2Ghz, 2G RAM and Nvidia 8400M GS with only 128M dedicated video ram. I managed to finish the Wind Waker, Twilight Princess(2-3 FPS on Hyrule field), Fire Emblems for GC and Wii, and those seem the only games I played on dolphin. But now comes Skyward Sword……
I do have windows. Ancient versions only support OpenGL, Older versions of dolphin run much faster on windows with D3D9, but newer versions appear no much difference, at least for games mentioned above. The nvidia driver for linux has made much progress.

**admin89** · 03-01-2012, 07:09 PM #7

OpenGL vs OpenMP
You may consider it as "speed hack" , you may gain a few FPS with some games

On windows 7/8 , I get 10C+ temp when using OpenGL . 30min test :
Idle : 32C (room temp : 30C)
Directx9 : 70C temp max
OpenGL : 79-80C temp max
I rarely use OpenGL unless I'm on the desktop
Don't know about Linux though

rpglord · (This post was last modified: 03-01-2012, 08:38 PM by rpglord.)

Dolphin already support quad cores,to be more precise,it uses 3 cores.
There are lot of games which does not have proper sound when using default HLE sould plugin. In that case you have to use LLE plugin. Problem which then arrise is that LLE plugin is very cpu damanding and many games become unplayable. Solution is to use option "lle on thread" which actually uses third core on the cpu. If you dont actually have third core in your cpu,you screwed !
So I would def suggest you choose i7 option...

sgsdxzy · 03-01-2012, 09:01 PM #9

Thank all of you for your advice. I plan to wait for ivy bridge so there's no hurry.
I had a test just now:
OpenCL and OpenMP don't make much difference here……OpenCL won't reduce performance. I had hoped that OpenMP will give a boost on quad core computers.
Anyway, openAL do give a speed up over alsa……although it has nothing to do with the problem.
Under linux, the peak temperature of cpu is 80C. Windows with D3D9 is 90C. The maxium safe temp of my cpu is 120C so I don't have to worry……

**admin89** · 03-02-2012, 12:50 AM **#10**

(03-01-2012, 09:01 PM)sgsdxzy Wrote: Under linux, the peak temperature of cpu is 80C. Windows with D3D9 is 90C. The maxium safe temp of my cpu is 120C so I don't have to worry……

What's your CPU model ? Desktop or Laptop ?
TjMax for Sandy Bridge is 98ºC and 105ºC for my laptop (1st gen)
I overclocked my e5300 to 3.6Ghz but it never pass 60ºC with dolphin . I have a big cooler Big Grin

(that's why laptop suck at cooling )
Whatever....80ºC is way too hot for any CPU .Your CPU lifetime will be shortened