Last year I purchased a Radeon 7770, and was
disappointed by the high idle power consumption, even when using two identical DisplayPort monitors. It was looking something like this:
Code: Select all
1 monitor 2 monitors
Core clock 300MHz 400MHz
Mem clock 150MHz 1300MHz
Core voltage 0.85V 1.2V
AC Power 65W 75W
Now I have a Radeon R9 280X. It's supposed to be architecturally almost the same as the previous 7xxx cards, so I wasn't expecting any difference, but I became curious today and tested it. Contrary to the previous results, I now get the following at idle:
Code: Select all
1 monitor 2 monitors
Core clock 300MHz 300MHz
Mem clock 150MHz 150MHz
Core voltage 0.85V 0.85V
AC Power 69W 71W
Whereas there was a 10W delta between 1 and 2 monitors with the 7770, now it's only 2W (note that the idle power consumption with 1 monitor is actually about the same as the 7770; the old figures are only different because I have changed other parts since then).
I would expect power consumption to revert to the previous bad behaviour if using multiple non-DP monitors, but I'm not going to test that.