Hi guys, I know we have a lot experts in here, so I could use your opinion about making some changes to my current PC.
CPU : AMD FX 6300
GPU: RADEON RTX 580 8GB
RAM : DDR3 2X8GB
HDD: 1TB
SSD: 250GB
So I want to upgrade performance. Thanks
To get modern and you'll need motherboard, CPU, and memory. Your current HDD and SSD would probably do for the interim. Whether your PSU, CPU cooling and case need upgrading is impossible to say since you didn't list them.
Otherwise about all you can readily do is upgrade to an 8 core FX processor in the FX 8300 family and overclock to it's limits. But viability depends entirely on your motherboard, which you also did not disclose, as it needs a robust VRM to handle it's power demands. You'll also need an extremely capable CPU cooler.
Whether it's helpful is a question though since all that gets you is 2 more Bulldozer cores, which isn't saying much. Games need high single thread performance so two more cores won't help with that very much. "Productivity" or "creativity" tasks...like video transcoding or image rendering...use more cores at once and so would improve performance more but still be very poor compared to modern systems. It's really a bad upgrade choice and a waste of money.
If your motherboard is capable of it just overclock your 6300 to it's limits and get pretty much the same benefit as overclocking an FX8300 for gaming. You should be able to get 4.7Ghz or more with proper cooling on a capable motherboard. But it still won't be enough to play high FPS e-sports titles with the big boys.
So if you're ready to jump into a new system it will be motherboard, cpu, memory at least and possibly PSU. New case, CPU cooler, NVME drive and GPU depends on your budget. GPU's are awful expensive.