You mentioned having problems running Premiere Pro and editing 4K videos on your old rig. I don't know what version of Premiere Pro you're using, but it loves RAM, especially at higher resolutions.
Not only do you need lots of system RAM for Premiere Pro, but also lots of GPU RAM. The charts on the Puget Systems web site are helpful when building a PC for Photoshop and Premiere Pro, but when viewing their recommendations, bear in mind they're testing newer versions of Adobe software, which tend to be very resource heavy.
For the latest versions of Premiere Pro, Puget Systems specify the minimum amount of system RAM as 32GB for 1080p video and 64GB RAM for 4K video.
Similarly, Puget state the minimum amount of on-board graphics card RAM as 4GB for 1080p and 6GB at 4K.
https://www.pugetsystems.com/soluti...be-premiere-pro/hardware-recommendations/#ram
You may be able to edit 4K video with 32GB system RAM and an RX480 with 4GB video RAM, but keep an eye on system resources and try not to run too many other large programs in the background. If you're using a version of Premiere Pro that's at least 5 years old, you'll probably get reasonable results from your Ryzen 2600 / RX 580 build, but you might have trouble with Premiere Pro 2023.
I recently upgraded an old AMD system from an A6-9500 dual-core APU to a 2600X and it's given the computer a new lease on life. When I swapped the 2x 4GB DDR4-2666 RAM for a 2x 8GB DDR4-3000 kit, the system failed to boot with XMP 3000MT/s enabled.
The spec for the 2600X (and the 2600) memory speed is max. DDR4-2933, so anything above this speed may need manual adjustment of the memory timings.
https://www.cpu-world.com/CPUs/Zen/AMD-Ryzen 5 PRO 2600.html
To fix the 3000MT/s XMP overclocking problem, I opened the BIOS and increased the CL (CAS) timing for each DIMM from CL16 to CL18 and the 2600X is now rock solid in MemTest86+.
https://memtest.org/
Obviously looser timings slow down the PC slightly, but if you're considering faster 3200 or 3600MT/s RAM, be prepared to play with the timings to make the system stable. You might get RAM to run at 3600MT/s, but 3200MT/s should be much easier to achieve.
Another thing to consider is if you add a second pair of DIMMs, you may have to drop your XMP speed down to 2600MT/s or 2800MT/s, regardless of the speed rating of the memory. Four DIMMs place additional loading on the IMC (Integrated Memory Controller) and make overclocking more tricky. It's not a good idea to mix dissimilar pairs of RAM. Even seemingly "identical" pairs of RAM with the same part description could well contain different memory chips and different SPD (Serial Presence Detect) speed timings. The best option is to fit 2 x 32GB instead of upgrading to 4 x 16GB, but this can be difficult on a restrictive budget.
As it happens, system RAM speed is less important for Premiere Pro running on AMD systems than on Intel systems, so you probably won't see a huge benefit from higher speeds in video editing. The graph below is for DDR5, not DDR4, but it shows the difference.
https://www.pugetsystems.com/labs/a...023-update/#Video_Editing_and_Motion_Graphics
See also this discussion about DDR4 from 2019.
https://www.pugetsystems.com/labs/a...formance-1528/#Premiere_Pro_Benchmark_Results
Adobe Photoshop has lower system requirements than Premiere Pro, but if you want to see the recommendations for the latest release, see below.
https://www.pugetsystems.com/soluti...ons/adobe-photoshop/hardware-recommendations/
It's worth trawling through Puget's older documents for details of hardware and software more closely matching your own.
Although Photoshop CC 2024 is very sophisticated, the subscription is expensive and you can still use the 13-year old standalone Photoshop CS6 to good effect.
I don't worry if some of my CPUs don't have a built in GPU. If the main GPU stops working, I fit an old PCI-e graphics card in its place. A GT630 from 2012 is sufficient to get Windows back up and running and show if the main GPU needs replacing.
You'll see a lot of people on forums suggesting you should replace an old PSU when upgrading, especially the PSU is outside warranty or of questionable build quality.
I use this list as a guide as to quality.
https://cultists.network/140/psu-tier-list/
If you're lucky, your PSU will be in Tier A - High-end (very expensive), Tier B - Mid-range, or Tier C - Low-end (more affordable). If your PSU is near the top of the list and you're on a budget, carry on using it until it eventually stops working. With any luck when the PSU dies of old age, it won't take out the rest of your computer.
If you're less fortunate, you may find your bargain basement PSU lurking down in the 'Tier F - Replace Immediately' category. Whether you take notice of this seemingly dire warning is up to you (and the depth of your wallet). Just remember your computer is living on borrowed time.
I have several ancient computers with low quality PSUs and they're still working fine, but I won't be too heart broken if they explode in a shower of sparks.
If this is your only computer, check the list and fit the best PSU you can afford.