Comparing a desktop to a laptop

Me and my friend would like to know if...


A desktop i5 2500k processor beats an i7 2720 or 2820 laptop processor in terms of performance?

or if a pny geforce 560ti desktop video card beats a 485m laptop card?

 

Both those mobile CPU's are more powerful than the 2500k desktop processor.

Graphics card wise, the 560ti is a bit more powerful, but not by much at all. They are pretty much equal here.

 

That's not true. From benchmarks, the core i5-2500k is fifth and i7-2820QM is 10th. The i7-2820QM is about the same as a i7-960.

For the GPU, a GTX 485m is about the same as a GTX 460 768mb, so a lot under a GTX 560 Ti.

 

R u sure bout the processors? The i5 has 4 threads and the i7 has 8

 

The 2500K is still better. Hyperthreading is nice, but it doesn't offset the significantly higher clock speed -- even with Turbo Boost, the laptop CPUs can't reach the default speed of the 2500K. You can see the relative performance of the two here and here.

That said, Sandy Bridge has brought laptop and desktop processors much closer than they have been in a long time. The desktop ones are still better, but only by 10-30% whereas before it was more like a factor of 2 (i.e. 100%).

 

What Alternai said, if you wanted something that came close to desktops for Clarksfield, you needed a xm CPU overclocked to pretty much the max it could attain.

 

Thats awesome info thank u guys

 

The 2500k would be a fair amount faster than the laptop processors (maybe 1.2-1.5 times as fast, depending on what you're doing).

Also, bear in mind that the sandy bridge processors have huge overclocking headroom (i5 2500k can be clocked at 4.9 and be perfectly stable with as little as a reasonably decent air cooler). It is true that sandy bridge have brought the laptops and desktops closer together, but that is mainly due to them focusing more on lower power usage rather than performance. Desktops can handle the power (and hence heat), simply put: if you fed the same power into a desktop sandy bridge as you would the previous generation, you could still slap all the laptop processors silly.

I might have rambled a bit but I hope it makes sense.

On the graphics front, the 560 ti should be a little faster. Also bear in mind that for the price of a 485m, you could get a desktop 580 or possibly even a 590 if it's on special offer (590's can usually be clocked back up to 580 clocks without a problem). A 580 or 590 would honestly trample all over pretty much anything laptops can offer.

On a side note, if price is no object then the 580m has just bee released, it's supposed to be pretty much a re-worked 485m.

 

As stated the performance is similar but you are paying for laptop mobility and mobility = the breaking point for laptops. And the best laptop GPU (485M) is equivalent to a desktop GTX 460. So you drop 1000 on 485M SLI, you could spend about 370 on GTX 460 SLI and get similar performance. Laptop processors are getting closer but of course desktops have way more overclocking potential, and the unlocked desktop processors are more realistic priced than the unlocked laptop processors.

 

like most of the posters above said (except that one guy whos probably drunk):

2500K is faster than 2720qm by a pretty big margin plus it can be oced very very easily even on stock hsf.

the 560ti is faster than the 485m but not 2 much.

prices differences between desktop and laptop counterparts are huge. 2-3x

 

Both mobile i7 will be faster than the desktop i5 in a scenario where the task is nearly arbitrarily parallelizable, the chunks of processed data for all parallel threads do not fit into the L3 cache and neither ALU or FPU have a lot to do.
(I can't think of such a scenario right now.)

In every other scenario the desktop i5 will be faster.

 

In short: Overall, the desktop processor is faster.

Mr. Mysterious

 

If neither the FPU nor ALU havee much to do then whatever you're doing can't be all that taxing in the first place. Most of the time, hyperthreading doesn't work. It's only in special instances where a core can do more than one thing at once, hence why hyperthreading only gives a marginal performance increase.