Haha seems like broken sensors on the GPU or some conflict with the software. You can always make a custom fan profile in a software like MSI Afterburner. It's weird if the fans are running by those temperatures because the system should shutdown at around 105 C as far as I know.
Have you tried re-installing the drivers and what not?
Yep, done all the gubbins. It spins up to JET ENGINE MODE during BIOS POST, leading me to believe either hardware sensor fuckup (oh god I hope not), or BIOS derpery (Please be this, bios is flashable).
Sapphire's TRIXX solution is unable to override the fan speed. Trying afterburner now.
EDIT: Afterburner's even more borked in readings than GPU-Z lmao