Upgrade or Replace XPS L702x

Howdy,

I am currently trying to decide whether to upgrade my laptop or to replace it. The machince is about 3 years old now and has been a great tool for field work and photography.
The requirement for a powerful laptop comes from using Civil 3D and Lightroom and I spend about 9 months of a year away at work. The type of work I do is slowly changing and while I will be using more efficient CAD software in the future, I will also start processing small amount of aerial photography data and scanner data, both which are too much for the current system.

Currently, the system is
Dell XPS L702X
Intel i7 2760QM
8GB 1333MHz
Nvidia GT555M 3GB
750GB 7200RPM HDD x2

I was thinking of upgrading the RAM and primary HDD to
16G Kit 2133 (8Gx2) G.Skill Ripjaws ($205) / 16G Kit 1600 (8Gx2) G.Skill Ripjaws ($182)
Samsung 840 EVO 1TB ($523)
*Prices from my local MSY store in Perth


If this were to work, there should be a considerable boost to system speed, however, reading the Dell sites, I'm not 100% sure it would work.
The other issue is ofcourse, is the performance increase worth the money compared to getting a new laptop, considering I can't upgrade the graphics or CPU.

Opinions and suggestions are welcome, I'm not a computer expert by any means, so forgive me if I ask questions with obvious answers.

Regards

The SSD would be a considerable boost but the RAM less so. If you would like to upgrade it regardless, go with the 1600Mhz kit.

Also, I am pretty sure the CPU is up-gradable as well, the question is, how good is the price/performance ratio of such operation.

EDIT: it is possible to upgrade the CPU, the two highest models you could have are Intel® Core™ i7-2820QM or Intel® Core™ i7-2860QM. On eBay you can have the 2860QM for little over $300, the 2820QM for around $100.

Also some DELL XPS L702X models have different version motherboards, make sure you double-check which one you have. If you will decide to go ahead with these modifications, you will need the XPS L702X service manual.

Thanks for the response.
The main reason for upgrading the RAM was because I occasionally get "Insufficient Memory" warnings while running certain applications. It wasn't a major priority though.

As I am not full bottle on all of these things, I can't see that the 2860 processor will give me a noticable boost. It is a similar clock speed, but has a larger cache. What kind of applications would perform better with that kind of difference?