the fastest laptops with intel mobile processors and fast nvidia chips are going to be the same performance as your current computer. so that wouldn't be an upgrade path for more performance, only mobile. if you haven't already, you can do some test projects on your current machine to see its performance with the 4k media.
if you are looking for faster performance to handle 4k, you would have to look at upgrading or replacing your desktop with a haswell-e build and going with a cheaper laptop for work. starting with the i7-5820K, it would be around 50% faster than the i7-2600, and a gtx 970 video card. you may not find a decent priced laptop with a ssd drive for your budget, so you would either have to find one you could replace the internal hdd with an sdd, or get an external usb ssd like the one from samsung.
Hey RoninEdits, thanks for your input.
Didn't realize that the mobile technology is lacking in performance so much in comparison to desktops...
If I decide to upgrade my current PC, there are only a few processors that are better on this socket (LGA 1155), the fastest being i7 3770k. Do you think there would be any noticeable difference if I replace the current CPU?
If I upgrade the graphics to gtx970, would the current processor present a bottleneck?
Do you think I will see a noticeable improvement if I buy the gtx970 and a good ssd disk while keeping the existing MB/CPU/RAM combo?
the i7-3770k would only be around 10% faster, so not really worth upgrading to. the other part of going with haswell-e for 4k media is the ddr4 memory, as it has twice the bandwidth to feed data to the gpu.
your current system is pretty well balanced, i dont see the gtx 970 helping unless you are using a ton of gpu effects and lots of lumetri color. if you are using mp4 files from your two cameras, the WD drive you have now should be ok. some people transcode their mp4 files to prores or dnxhd/r to get better performance. those formats/codecs place less demand on the cpu & gpu, but use higher bitrate that makes larger file sizes. if you were using files like those prores or dnxhd, then depending on the bitrate, a faster drive like the ssd may help performance. premiere also has a setting in the program monitor for playback resolution, changing that from full to 1/2 or 1/4 will lower the demands on the cpu, gpu, and memory, increasing performance.
if you can do some test projects on your current system, you can monitor the hardware with windows task manager or resource monitor and gpu-z. once you know what you are dealing with, you may have a better idea of what you want to upgrade to.
Where are your project files and where do you export to?
Thanks for the answer and advices.
So it seems that apart from the disk drives, it doesn't really have sense to upgrade my current desktop PC. The only question is, how well it performs during a 4k edit...
Would try it myself, but I just did a fresh install of windows 10, and i still have to buy and install the new premiere and after effects (i worked only with CS6 before). Currently I'm on a business travel, so that may take a while.
Anyone with similar specs care to comment about the performance when working with 4k files? Also, will I see a significant decrease in performance if Use a 4k monitor instead of full hd? Would my gpu even be able to drive it?
The other option is to buy a new PC, but I'm afraid this will eat away most of the budget for the notebook...
Thanks for the transcoding and lower resolution tips. Never tried transcoding before editing...
@Bill: I usually copy the files to one of the ssd drives, depending which one has more space, sice they're both only 64gb... I then export to the 7200 rpm hdd.