Mobile i7 vs Desktop i7

Hey all,

this is probably a stupid question.. but I was wondering.. how much less performance do you get out of a mobile i7 CPU (say for example the 740QM) compared to the equivalent desktop versions?

I'm currently trying to decide between a gaming laptop and a new desktop, and i'm working out the pros and cons

Anyone got any links to benchmark comparisons or anything?

Thanks for any info.

 

Gaming desktop always gives you better value. The cost of getting a core i7 with maxed out components is way higher than building a desktop with more powerful specs.
Unless you want mobility, taking your computer everywhere, then buy a laptop. Otherwise, Desktop wins in every other aspects.

 

Yeah I definitely need portability.

I'm just worried that i'll be disappointed with the performance of the laptop, compared to the desktop I have now which has a Q9400 CPU.

 

Power price portability. Pick 2.

 

Ok, power and portability. I'm willing to spend the money to get something epic. Just not sure what to get

 

What are doing with that Q9400 CPU? Gaming? Email? Heavy encoding? Your usage patterns are going to determine whether you'll feel bottlenecked by any given laptop CPU.

 

All of the above I do a lot of gaming and video editing.

 

Hmm. I don't know how a current mobile i7 stacks up against a desktop C2Q, but I think some of the more powerful mobile i7s (840qm and higher) should actually be faster. Not as much overclocking room, but mobile i7s can't really be overclocked, anyway.

 

Mobile i7s can be overclocked by increasing the BCLK value. This can be done via SetFSB tool. In order to do so, You need to know exactly, which clock generator does Your machine use. The only way of checking it is opening the laptop and having a look at the motherboard, looking for a chip labeled ICS.

 

Hmm.. so can anyone with the i7 740QM who has owned a desktop C2Q tell me... does the 740QM perform noticeably worse than your average desktop C2Q?

I know it's a stupid question and it's extremely hard to gauge.. but.. i'm gonna ask it anyway Just wanna make sure that i'm not gonna regret getting the M17X, or G73, or whatever I decide to get.

 

Or SLG, or RTM. ICS isn't the only PLL manufacturer.

To be honest, from the benchmark craze that went through the hardware forum here when the original i7 mobile chips were released, there wasn't a huge difference between my aging budget Q6600 and my newer i7-720QM (base quad). Sure, the i7-720QM is better, but not by the amount that it's all hyped up to be.

At any rate, the mobile i series processors are FAR behind their desktop counterparts. But. They are still usable, and fast enough.

 

That's that I wanted to hear. Thanks

 

Just saying, but based on cpubenchmark.net charts, the Q9400 is about as powerful as the i7 840QM..
Though I have to say that having a mobile ''powerhouse'' is pretty neat

 

if u really want a desktop CPU , get the new Clevo X7200.. u'd get a desktop i7-975, 980X+ GTX480M SLI and won't have to worry about performance... personally , i'd save 1K and get GTX460M SLI if u can... perfect for your uses...

 

The 740QM is behind the desktop Q9400 by a bit. Even though the Core i architecture is more efficient, your C2Q is over 50% faster, way too much of a difference for the i7 to catch up to. And don't forget that overclocking desktop processors is very simple and effective. My desktop i7 860 was at 4Ghz. My desktop Q8200 was at about the same. In fact, it would be foolish not to overclock a desktop processor, even if by just a little bit and leaving all other settings and hardware the same.

 

Doing this causes instability and can actually degrade real world performance.
Overclocking should be done the proper way in the BIOS.

The i7 740QM is no doubt a fast chip except it struggles to keep up with the desktop parts mainly due to clock speeds. For a 45w tdp it performs damn well and in gaming there isnt a huge difference between this ur C2Q desktop cpu's. However the 920-940XM is the way to go if video encoding is your thing. It is just as powerful as the desktop i5 750 which is pretty fast.

 

In certain situations the i series can knock the socks off the core series, this is because the memory controller is actually inside the CPU and not in the northbridge. If you use programs which make very frequent updates to databases stored in memory or something along those lines then expect to notice a difference.

 

Thanks for all the info guys.

I'm no closer to making a decision.. but it helps

 

I don't think the integrated memory controller is that big of a deal performance-wise on the core i processors. AMD added an on-die memory controller to the Athlon 64 which was its main difference compared to the Athlon XP and performance increased dramatically. But in Intel's case they stuck with the memory controller on the northbridge for 5 more years until releasing the i7 in '08. The northbridge-based memory controller was just not limiting performance the way it had on the Athlon XP. Hyperthreading and other tweaks to the design are what gives core i a real performance advantage over core 2, not the memory controller. The on-die memory controller is really just superfluous from a performance standpoint.

 

You can get a laptop with a desktop i7 if that will make you happier

The battery life of course will not be insane (at least not insanely high....). Look up the Clevo D900f or Sager NP9280/NP9285. They are not a fashion statement, but are truely mobile workstations.

The i7 840qm will be comparable to the Q9400 in most situations. My QX9300 is even comparable most of the time (just "old")