Comment # 20 on bug 76490 from dex+fdobugzilla@dragonslave.de

I can confirm: drm-next-3.17-wip + new ucode doesn't make any difference.

Testscenario:

* Built/Installed new kernel, copied new ucode into /lib/firmware
* Built new initrd
* reboot with "nomodeset" and gfxpayload=text into multi user runlevel
* modprobe radeon drm=1 modeset=1

Monitor went black (but shows connected DVI), system is unresponsive.