Originally Posted by danix
Yes, we normally expect this GPU to be able to switch clocks for power management purposes. When we tried to reproduce your problem we saw that our system changed clocks normally.
Dell has meanwhile exchanged the FX2800M against another FX2800M.
Unfortunately, this did not (!) change anything regarding Linux. Also the new FX2800M runs constantly at maximum frequency.
Dell has assured me that the do not modify the FX2800M behaviour by some electronics or switches on the cards.
Dell has asked me to perform some more tests under Windows 7 - with the GPU-Z tool. We tested different settings for the power saving options under Win 7.
With the recommended Win 7 "balanced" mode the FX2800M always runs at maximum frequency. Its temperature accordingly rises from 40 degrees Celsius to 58 degrees celsius - without any load - the PC is running practically idle. Disonnecting the power supply leads to a frequency reduction by one step - there it remains constant. This is the behaviour one sees under Linux, too.
However - if you you enable "prolonged akku time" (German: "Erweiterte Akku Betriebsdauer"), i.e. the maximum energy saving option under Win 7 and if you then disconnect the power supply the graphics card then changes it frequency step by step down to 200 MHz. However, it would not do it with the power cable connected.
I have attached the log-files from GPU-Z.
Dell has tried to do the same with an FX3800 on an M6500 and there the frequency changes are as expected - but only after you once activated the maximum power saving option.
Any ideas what the behaviour under Win 7 could mean ?
By the way: Dell is now going to fetch the M6500 to its lab in Halle, Germany, to perform further tests.