i7 620M vs. 720QM

[grbac]

Any benchmarks, reviews yet?

I'm planning on buying a NB and I'm deciding between these two. I know that this is a comparison of quad vs. dual and it has been discussed many times, what I'd like to know is if the difference in working frequency and while TB is on will have any impact on performance.

Enlighten me please...

EDIT: Added poll...

[Euclid]

Depends on what you plan to use it for. For my usage pattern (development) the 620M is the better choice:
- Lower heat loss (32nm vs 45nm, dual vers quad core)
- Higher maximum instructions/second due to higher frequency
- The build process (compiler/linker) has too many dependencies and more cores do not speed up things linearly. E.g. linker/compiler cannot take full advantage of the 4 cores.

However if your application (e.g. games) can take full advantage of the additional cores and you don't mind the additional heat loss, a quad core might be the better choice.

Regards,
Mat

[grbac]

A bit more information then... Laptop in question is Clevo 860CU. It will be used for gaming, internet and other general stuff. But mainly I'm looking for the one that will be better for gaming, other stuff is secondarily. I don't mind the heat.
Thanks

[IntelUser]

I think they will be pretty close, even in heavily multi-threaded apps. In lightly multi-threaded apps, it'll be 620M that's faster, no question. But with many threads, its 100% more cores vs. 77% more frequency.

Clock speed advantages of 620M over 720QM factoring in Turbo Mode.

1 thread-19%
2 thread-27.5%
4+ threads-77%

But is the 720QM worth it for massive TDP differences and heat? In my mind, the top 3 i7s(that are relevant) are now 920XM, 820QM and 620M.

[sreesub]

i would go with 620m. laptop tdp is makes a big difference in battery life and heat generated. Plus I am not sure turbo mode works for every load. Raw cpu speed would ultimately work better when you are doing more than 2 tasks.

I am hoping sandy bridge cpu's have lower tdp quad cores and at higher base cpu speed as well.until then arrandale would be better buys unless you are looking at DTR.

[worx]

Would the quad core be faster for extracting large winrar files around 10GB?

[cloudbyday]

If winrar (or whatever extracting program you use) allow for multi-threading.

[QuadAllegory]

If winrar (or whatever extracting program you use) allow for multi-threading.

Isn't that primarily limited by your HDD speed?

[tilleroftheearth]

QuadAllegory,

Yes, the HD speed would be one limiting factor, but WinRAR does support a multi threaded CPU, so it is faster the more cores you have (don't know if it does more than two though, I should test this tomorrow).

[worx]

QuadAllegory,

Yes, the HD speed would be one limiting factor, but WinRAR does support a multi threaded CPU, so it is faster the more cores you have (don't know if it does more than two though, I should test this tomorrow).

Do you have both the quad core and dual core i7? That would be great if you could do a test. How do the wprime times compare?