Changes on FGPR for GPUs or GPU problem?

Hello,

I have run Einstein@home now on my AMD RX 580 for about 1.5 years with everything being as always.

Now I got back into office from a long weekend and the fans spin at high / max rpm, while the processor load is lower (see attached screenshot)  So I thought there might be a problem with the cooling and the card ist thermal throttling but the runtimes are still the same and I can't check the temperature as macOS is not able to do so with a non Apple branded card. So I am very confused now about what's going on? 

My initial idea is to buy new heat paste but maybe better check first here if there was some code optimisation that could cause this behaviour or wether some of the geniuses among you guys has another idea :)