Ok, so here is the tool Gorod just tested above.
It is simply called EMBD (Ellesmere's Backdoor) and it increases the power limits from the stock figures. It also raises the maximum allowed MEMCLK limit from 2250MHz to 2500MHz. It re-configures the display driver and makes no changes to the hardware itself. The functionality of the program is purely "fire & forget" and it is executed only once (once to apply and once to remove, if necessary). Once you have deployed the tool you can delete it if you feel the need to do so.
It changes the configuration so that the new -50% PowerTune setting (in WattMan) is the same exact thing, as the stock configuration (at ±0% PowerTune) was.
After this tool has been deployed, the new power limit figures are:
PowerTune -50% = 110W, ±0% = 165W TDP, +50% = 247.5W TDP. The current limitations also reflect the same changes, so it is likely that you'll actually hit the current limitations of the VRM controller itself before you hit the driver limits.
The voltages or the frequencies have not been changed from the default settings.https://1drv.ms/u/s!Ag6oE4SOsCmDhDIoWNpvaMKq8OtE
NOTE: Both of the changes (Apply & Clear) require a reboot. Also the program does not support multiple adapters, regardless if they are in standalone or in CrossFire mode.
EMBD V1.2 https://1drv.ms/u/s!Ag6oE4SOsCmDhERPkAmTcANOYbnk