Is my GPU going to die If I don't keep doing this?

Hellooooo.

A few months ago, I bought an AMD RX580 8GB SP graphics card to replace my old AMD RX560 2GB, but it turns out my power supply doesn't have an 8-pin connector to power it properly. It's temporarily connected to a 6-pin connector. I was told that connecting a graphics card like this to a 6-pin connector is practically dangerous, so I made some adjustments to the graphics card using MSI Afterburner.

I've limited the power to -30%, the core voltage to 1031 mV, the clock speed to 1284 MHz, and the memory clock speed to 1750 MHz. I'm trying to keep the graphics card from drawing more than 75 watts from the power cable, hoping that the PCI Express slot on my motherboard will provide the rest of the power needed for it to function correctly. When I run a stress test with AMD Adrenalin, it shows that it consumes 4 watts in standby mode and up to 70 watts during the test, but I don't really trust it. I don't know if it only shows power coming from the cable, or from the slot, or combined, so Idk. I'm pretty sure it shows the power consumption FROM THE CARD, but I don't know which source that power comes from, and I really want to avoid burning the cable. When it's warm in my country (33C°-39C°) my GPU stands by at 41C°-44C°, and when it's cold (0C°-20C°) it stands by at 23°C-29C°. Currently it is at stand by at 28C°-29C°.

My question is: Is this power consumption sufficient to protect the graphics card, my computer, and my house until I can replace the power supply? Am I exaggerating a bit, perhaps? How much do I have to *actually* limit my GPU to keep it safe? This is my very first time owning quite a strong GPU and I really, really don't want to mess it up, so I don't mind being extra careful. I want to take care of it.