Comment # 233 on bug 66963 from Francisco Pina Martins

@lockheed:

The frosting screen forced me to do a reboot, since after it happened, X became
unusably slow.

I am using the stable version of mesa: 10.1.3-1
I have used mesa-git in the past (well before DPM), to squeeze a bit of extra
performance from my card.
But since this is no longer my main machine I have reverted to stable packages
in order to lighten up the maintenance burden.
Let's hope DPM starts working fine on your card too.