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[madbiologist <825989@xxxxxxxxxxxxxxxxxx>]

Radeon dynamic power management was introduced in the 3.11 kernel and
further refined in the 3.13 kernel used by Ubuntu 14.04 "Trusty Tahr".

** Changed in: linux (Ubuntu)
       Status: Incomplete => Fix Released

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https://bugs.launchpad.net/bugs/825989

Title:
  radeon driver power management is very bad: GPU always runs at maximum
  clock speed

Status in X.org XServer - ATI gfx chipset driver:
  Confirmed
Status in “linux” package in Ubuntu:
  Fix Released

Bug description:
  Opensource radeon driver's power management is EXTREMELY bad, at least
  in default OS setup.

  Configuation:
   Virtually any (K,X)Ubuntu (32, 64) so far. Latest tested is Xubuntu 11.10 alpha but problem also exists in 11.04, etc.

  Problem
   I own 2 x AMD HD 5770 PCI-E graphic cards. When I use Radeon opensource driver, power management is REALLY, REALLY bad. Both GPUs are always running at maximum - 850MHz core and 1200MHz RAM. Never reducing frequency, ever. Even if load is minimal or one of cards is unused at all (secondary display detached and no other loads on secondary GPU). This leads to unreasonable power dissipation for nothing, CO2 emissions, etc. Cards have leds to indicate load, each supply phase with it's own led. I can see GPU supply runs all 3 phases all the time on both cards.  In fact, it's quite unpleasant to get ~100W of heat for nothing when it is already +30C around. Not to mention GPU coolers are making some noise and power consumption is bad.

  Expected:
   fglrx is much better at power management. Under exactly same scenario it instantly downclocks both cards to 157MHz core and ~340MHz RAM, drastically reducing power consumption (I can even see how 3rd phase of card's supply is shut off on it's LED after fglrx loads and hear that cooler slows down). I believe opensource Radeon should do the same, in default setups. After all, it can get frequencies from the card so it's probably not that hard to set thses frequencies as well. Actually it looks like if Radeon actually capable of managing power but this does not works for some reason yet.

  ProblemType: Bug
  [deleted] - erroneously pasted this from wrong (fglrx) package.

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