M2400: P8600 vs. T9400

Image you're using your notebook for things like 3D CAD, photo and video editing and of course for travelling. For my purpose I think the M2400 with its 14,1" monitor should fit perfectly. The perfect combination between mobility and performance.
Now I have to decide between 2 processors. As you know the P8600 isn't available and even Dell couldn't tell me if it will be available in the next weeks.


As you know the M2400 can only be ordered with the following processors:

• P8600 (2,4 GHz, 25W, 3MB Cache)
• T9400 (2,53 GHz, 35W, 6MB Cache)

So which one would you choose and why? The price difference is about 100$ (71,4 EUR).

 

the only reason for opting for a P-series CPU is if you are inane about battery-life. which clearly you aren't (or at least you shouldn't be) because you are opting for the power-hungry nVidia Quadro for good performance in your video/CAD work.

get the more powerful T9400 to go with your more powerful GPU.

 

Is there such a performance difference? I know that the NVidia is power hungry but combining it with an also power hungry T9400 equals even less mobility^^

 

Too bad they dont have the P9500 like with the E6400. The performance difference isn't much but then again the battery life doesn't really go down much either. If you do a lot of CPU intensive stuff then by all means upgrade; however, I think most software the CPU isn't the bottleneck.

 

I would advise to go for the P8600. Both CPUs can be undervolted, but the P8600 has a lower TDP, so it'll give you lower temps and more battery life, when you run CPU-intensive tasks such as Audio-Video/Image editing on battery power.

Cache doesn't really help in audo-video/image editing, so save the $100, and invest in more RAM or a fast HDD, which are sure to boost performance when running the above tasks.

 

Why not? And whats that cache levels slider in Photoshop for?

Thanks.

 

Ummm.....PS cache levels have NOTHING to do with CPU cache..

In PS, the higher the level, the more levels of image size (sich as 100%, 50%, etc) PS will cache in RAM so that redraws are quicker...

CPU cache is basically memory for the CPU that it uses to store data that it's working on.

On CPU-intensive tasks such as Video processiong, cache does matter because the CPU is able to pull more data from RAM and store it in the cache, allowing it to process the data much quicker

 

Okay thanks for the info.

 

have to disagree with this. i think in precisely video/image editing where the same data is manipulated in many different ways would increase cache hits / efficacy.

in photoshop, say applying several transformations to an object ... having this object data in the cache will make the calculations go much quicker.

the bigger the cache, the more speed boost you can expect to see.

if you are not a stickler for battery life (and u shouldn't be if you are looking for performance / at non-integrated graphics), get the T9400

 

In photoshop, you basically need more RAM so that you can manipulate large images and avoid using the HDD for cache.

You need fast CPU frequency to basically apply filters, render video, etc quicker than normal, and I don't how cache comes into play here. In video-editing, to keep the audio-video streams in sync, you need a fast HDD.
Again faster CPU frequency, and if application is multi-threaded you'll save alot of time.

But an extra 3MB cache, how much can the cache store, how many instructions can the L2 cache grasp, next in order to the L1 cache ? --> 3MB or 6MB, which is still significantly less. Plus, more L2 cache, more latency. On average, more than 90% of all memory accesses are caught by the L1 cache. Less than 10% have to go on to the L2 cache. And a bigger L2 cache is a slower cache. Similar to memory, which is bigger, hence it is slower.

Cache will come more into play when transferring small bits/bytes, such as when extracting and compressing using winrar, etc, where CPU has kind of complete authority, the CPU cache doesn't get any instructions from the OS, as to get this bit first or get that byte first. When the OS needs to give instructions, it goes to the HDD, and partially to the RAM. High CPU frequency improves and quickens the process of these instructions going here and there. CPU is the brain, which gives instructions and controls the transfers between the HDD, RAM and the GPU.

EDIT: 1MB vs 2MB vs 4MB Cache