6 pin power connector

I am using a 6 pin to 8 pin converter to power my GTX 1080 (It has a single 8 pin connection on it) and my PSU doesn't have any 8 pin slots (Rocketfish 550w PSU). The GPU works fine, but one of my colleagues suggested that the converter might be causing the GPU to be underpowered. I'm not sure...

Hello. I've recently changed my Palit GeForce GTX 1070 Ti JetStream GPU (which was perfectly fine, i thought it was broken since it was a 2nd hand deal) with an ASUS RTX 2060 RoG OC. So basically, when I changed the fan speed of the Palit GTX 1070 Ti, the PC would make an electrical noise, and...

I'm on a slight budget and was wondering what the best priced psu is at this time. All I need is a psu that is above 450w and preferably tier 1-2 and maybe 3.