Question Are these PSUs safe to convert from 6pin PCIE to 8pin?

[kumbula]

Hello,
I have a Raptoxx RT600C with 1x6 pin PCI-E and a Chieftec GPS-550AB A with 2x6 pins available, but I'm currently looking into upgrading my GPU to an RX 580 or something similar in performance which requires an 8 pin PCI-E. I found out it's possible to convert 6 pins to 8, but it's dangerous if the PSU is of poor quality. I'd like to ask for your help to decide whether either of these are suitable. I could buy new, but I'd like to save money where I can. I might look into finding a good quality used PSU if these are not good enough.
Pictures of the PSU labels.

My would-be system:
i5-3470; 12 GB DDR3
RX580 or something which can match the CPU's fps on AAA games with med/high settings(I'm researching that at the moment. I'm aiming between 40-60 fps)
1x HDD 1TB 1x SSD 250-500GB

Thanks in advance.

 

[Barty1884]

If the PSU doesn't have the appropriate connectors for the hardware you want to run from it, that's the biggest sign you need a new PSU.

While dual 6 pins can be adapted to a single 8 pin, I wouldn't be comfortable doing so on either of those units.