suitable system for After Effects

Lots of good points have been provided, I'd like to offer something a bit different by exploring the type of work you intend to do with AE.

If you'll be working with a max of HD1080 source files; for both stills and video AND you'll be doing flat-design or design with gradients that do not utilize lots of heavy effects and 3D, then you should be OK. Let's see how you progress for the next three months in terms of technical and creative achievements and if you can ear some money to save for an upgrade or new laptop then, even better.

If you can afford only one upgrade now, I'd suggest to go with the SSD route. The SSD can be repurposed/re-used should you purchase a new laptop. Ditto with RAM although whether it can be used in a new laptop is possible but less likely - but this is something worth checking out before splashing cash on additional RAM for your current laptop.

You should also learn to work efficiently with AE and this is regardless of how powerful your system is. Learn how to set up your Comp Panel and Preview Settings to suit your varying needs and system.

I'm almost sure that the laptop you have now can add at least 16GB of RAM, start with that if what you need is to do medium work in After Effects. RAM memory is usually the respiratory and momentary solution for some systems not as modern as yours. But if you are determined to get a new computer, then Slazam already gave you some guidelines.

In general, for After Effects performance, the most important thing is clock speed of the processor. In some future versions of AE, the number of cores will matter a bit more than they currently do (the AE team has been talking publicly about how they're developing a more multithreaded renderer).

Also important is RAM. MINIMUM system required RAM is 16GB, but the suggested minimum is 32.

GPU is a bit important too as a number of effects render entirely on the GPU (the VR effects and a number of third-party plugins) or can be accelerated by a GPU (Fractal Noise and dozens of others), but this doesn't have to be crazy - just something decent like the 1000 series from NVIDIA.

Having SSD instead of HDD (and multiple ones, if possible, so your cache can be seperate) is also helpful.

So, knowing that, it should help you know for yourself what you can improve or not.

The question of whether you will see any performance improvements (beyond the usual "new computer" boosts that are expected) cannot be answered without any info about a) your current computer and b) what kind of projects you plan on doing. This is way too specific in AE and the limitations of laptops don't make things easier. Projects with lots of footage may suffer from slow harddrives, effect-heavy work may not be fun with a weak GPU and anything else you can imagine. Per se of course you could upgrade the RAM to the full 12 or 16 GB if the system allows and you can afford it. the rest will depend on the finer details.

Mylenium