amd radeon multi-monitor power draw

[Magic Carpet]

anyone tried forcing it to 2D/lowest p-state, results? Artifacts, anything?

i.e. 300/150 vs 400/1400 or smth

 

[Borealis7]

according to one chart i see right now, AMD's multi-monitor power consumptions have traditionally been high-ish, it might be an architectural drawback of GCN.

 

[Magic Carpet]

I am curious, if anybody here "forced" the lower clocks and experienced any issues. I am going to test this myself, when I get around to it. Just thought, somebody may have already done that to GCN

 

[james1701]

I tried it with my 7970's and it did not like it one bit. I had artifacts on the desktop and some freezing. I gave up and left them at stock clocks.

 

[TurtleCrusher]

I had the same experience with my old 6870. Haven't tried it with the 270 yet.

 

[Magic Carpet]

Thanks guys, and so I thought. Kind of disappointed really.

Right now one of my 270's pulling over 30 watts more than Kepler, using just two screens. Grrrrr.... if I get to mod the bios, I'll update this thread. Still no idea, why the memory clocks need to be this high, though (1400 Mhz). Stupid AMD

Love the zero-core mode, though. Fingers crossed, it gets fixed in the next GCN iteration.

 

[Jovec]

AMD tried idle clocks for multi-mon and then were forced to change it due to crashes/failure to resume. Can't remember if it was 7000 series of 6000 series. There was some talk of using idle clock if both (or all three?) monitors were the same res, but that never happened afaik.

 

[96Firebird]

If you don't use both monitors frequently, keep in mind the Win+P shortcut to quickly change between single and multi-monitor setup. I used this quite frequently when I had my GTX 460 hooked up to my TV as a secondary monitor. Only used it when watching movies, etc...

 

[xorbe]

Same prob with multi-monitor on my nv card too, and nv + 144Hz, and nv + Media Player Classic HC ... all of them spin up an extra 80 watts!!! (Titan) So don't feel too bad about woes on the Radeon side. Really you'd think they would both have these things ironed out in 2015 already.

 

[Jovec]

If you don't use both monitors frequently, keep in mind the Win+P shortcut to quickly change between single and multi-monitor setup. I used this quite frequently when I had my GTX 460 hooked up to my TV as a secondary monitor. Only used it when watching movies, etc...

When I tested this on my AMD 7950 (?) it doesn't lower power draw. You have to unplug the second monitor cable from the GPU to get the lowest idle clocks. It was about +30w with two monitors connected, as the GPU ran a 500/1200 instead the lowest idle clocks. You should be able to confirm this with a utility that monitors GPU core/mem clocks. Even with Win+P selecting single monitor, clocks would still be 500/1200 as long as the second cable was connected.

Same prob with multi-monitor on my nv card too, and nv + 144Hz, and nv + Media Player Classic HC ... all of them spin up an extra 80 watts!!! (Titan) So don't feel too bad about woes on the Radeon side. Really you'd think they would both have these things ironed out in 2015 already.

What res and how many monitors? My 780 with two 1080 monitors runs at 324 core/mem with either 1 monitor or 2 connected at 2D / desktop, but it's common for GPUs to clock up to a mid-level state for certain decoding tasks (flash, for instance). I guess 144Hz might need higher idle clocks too.

 

[TurtleCrusher]

I guess 144Hz might need higher idle clocks too.

I'd guess that's the main reason. 144 requires 2.4x the load of 60.