What are the options for upgrading a PC for a small budget?

Question

motherboards

There is an old computer on the motherboard LGA1155.
It has 2 slots for RAM and is generally satisfied so far.
Build on i5 3330, RX 570 4GB, 2 DDR3 rams, 4 GB each, 1600 MHz.
The other day there was a need to upgrade the assembly for more convenient video editing in Adobe programs.
I plan to use Premiere Pro and After Effects side by side, working in one after the other.
As for the videos themselves - FullHD, 60-120 fps, 30k bitrate.
If the processor still pulls out some kind of processing, then the RAM is running out.
And here 3 upgrade options start:

• Take 2 dice of 8 GB of RAM, in the future choose a motherboard for new processors. But at the same time, old 4 GB dice will remain out of work
  
• Take a motherboard for the 1155th socket with 4 DIMM slots, insert old dies into 2 and additional 8 GB each into 2 others. In total, 24 GB. But at the same time, the possibility of upgrading to new processors with other chipsets is blocked.
  
• Do not touch the motherboard, replace the RAM and take the I7 2600 (k) processor.
  

Unfortunately, my knowledge of the topic is not enough to choose. Yes, and maybe there are other options.

Answer 1

Take 2 sticks of 8 GB of RAM cheaper than DDR3 for the current mother of the processor. Start working, earn money for a normal full-fledged upgrade to a modern, up-to-date platform.
And by the way, it is quite possible to get by with relatively small funds, in the simplest case, you will need to start with percent + mother + new 16GB RAM.
AMD Ryzen 5 3600X
Gigabyte X570 Aorus
16GB Corsair Vengeance LPX
~30,000 without shipping. Well, here, of course, you can immediately save on the process, but I would not touch the motherboard and memory.
Oh, yes, and we didn’t write the power supply at all. You need to think whether your current one will pull.
But investing in an old generation motherboard is not a very good choice. Unless there is a very interesting and profitable offer from the seller.