i7-740QM or i7-840QM?

I am currently looking at buying a sony f-series laptop and was wondering if upgrading from

Intel® Core™ i7-740QM processor (1.73GHz) with Turbo Boost up to 2.93GHz

to

Intel® Core™ i7-840QM processor (1.86GHz) with Turbo Boost up to 3.20GHz

for $190 more is worth it?
I will be running programs like microsoft visual studio 2010, adobe products(photoshop, dreamweaver, flash, etc.), microsoft office, blender and other 3D graphics programs. Possibly some games like starcraft 2 but not often.

 

The 840QM has a 7% clockspeed advantage over the 740QM; to put that in perspective, if it takes ten minutes for the 740QM to process something, it will take the 840QM 9:18 (that is just a surface level comparison, not meant to be scientific). Not worth $190 IMO . . . better off either saving that money or investing it in more RAM or an SSD.

 

Thank you, i'll definitly go with the 740QM then.

 

a 7% is 7x4 cores=28% performance increase (again non-scientific surface level comparison)
i will agree with charles that the price difference is quite big but adobe programs you mentioned do work well with mulitcores.
also if you do a lot of encoding 28% may be a significant difference.
depending on your budget and needs 28% may not be a bad performance gain imho

 

@trvelbug

You can't just multiply the clock speed increase of 7% by 4 and call it 28%. In fact, I doubt that you'll even see 28% improvement with the 840QM when all cores are running full throttle. The processor has a tendency to clock down when the temps go up and a lot of it depends on the cooling system.

For single threaded applications, the 840QM will provide a noticeable boost, but you won't really miss it. The cache really shines when encoding and making use of the SSE instructions.

Personally, I chose to go 840QM over the 720QM offered on the Envy 17 because the 840QM is a higher binned processor. Thus, as binning goes, it should be more efficient than the 720QM at the same speed and produce less heat.

Also, I plan to do a lot of CAD and will really push my Envy 17 to the limits. The SSD was not worth it to me because I want to wait till the Gen3 Intel SSDs come out and upgrade that myself.

 

I don't believe it works like that. If both chips are using all four cores, you don't add the difference on each core. A stock 920XM isn't even 28% faster in 4-8 thread programs.

 

of course the relationship is not that linear and it was just for illustration purposes.
it would only hold true if the architecture is perfect and if the sofware took full advantage of the hardware.
i was just trying to show that the increase in performance should be considered amongst all four cores ( i dont consider virtual cpus much), especially in prgograms that make good use of mulitcores as the OP mentioned.
with regards to metrils comment about throttling and thermal issues, i believe this is more a laptop design issue than a cpu issue, ie a laptop should be designed to handle the tdp's of the cpu's it is made for.

 

Total Difference on 1 core:
740QM = 1.73
820QM = 1.86
Difference = A/B = (1.86/1.73) = 1.07

Total Difference on 4 cores:
740QM = (1.73)*4
820QM = (1.86)*4
Difference = A/B = 1.07

Stil 7% faster?

Either you're vastly superior to me in mathemathics, and I have wasted 4 years of my adult life learning it, or you're intentionally deceiving me to think as such, as Part 1 of your 3-part plan to rule the world.

I'm leaning towards the latter right now.

 

your logic is sound!
i was basing my statement on a converstion i had with a post production artist. i asked hime why he preferred using (dual) hexacores to (dual) quads at the same ghz since the price difference was quite big. he said you should not only consider the speed of a cpu but also the number of cores since they make a big difference in video editing and compositing.
i then asked him about the not so impressive differences of quads and hexacores in benchmarks and he said video benchmarks usually just deal with encoding files. in vid editing and compositing you do much more than that like edit differnt inputs from different sources, render effects, change perspective, render transitions, use mulitple layers, mix sound, etc and then encode. benchmarks as they are right now cannot include the complexity of the editing process and will not show the full benefits of multicores.
although he was talking about workstations, the logic should hold true for notebooks too.
am i wrong to accept his logic? but i also see the obvious logic in fishsticks statements. i would like to know since im planning on upgrading to a 920xm and am expecting a signifcant boost, at least with my video editing.

 

Oh, so you're not planning to rule the world

Well, according to Cinebench R10 (Multi), you should be seeing a 34% performance gain. Not sure how benchmarking scales to real life situations though.

Perhaps for the $1,000 you'd pay for the i7-920XM, you could assemble an i7-860 rig, that would work faster than your laptop?

 

lol!

im looking for a 50% performnce gain which should be possible by the guys logic. but now you made me think

hopefully as the x40 m's come out the original i7 quads will get cheaper. or if the gurus get setfsb to work with my laptop i could settle for a 840qm