2nd Display adds 10C to idle GPU Temps?

[JJ24]

Is this common?

System specs should be in my signature.

Right now with 2 displays on (24" Main and 18" Secondary) my Idle GPU temp is 51C
If I disable that 2nd monitor the Idle GPU temp drops to 42C.

Haven't yet tested it while gaming with the 2nd monitor off, when I was playing Bioshock Infinite earlier the Load temps on the GPU were 71C at 98-99% load the entire time. That was with both monitors on, with the monitoring stuff on the 2nd monitor so I could see it.

**Edit: Just disabled 2nd display again while watching the Afterburner monitoring data....
2 Displays:
52C / 0.949v / 500mhz core clock
1 Display:
42C / 0.808v / 300mhz core clock


Addtl data:
Room temp is approx 25C
CPU Temp at idle is 34-37 across the 4 cores.
Case has the following fans: 2x140mm Front intake, 1x140mm Side Intake, 1x140 Rear Exhaust, 1x140mm Top Exhaust

 

[djsb]

That is normal, because the memory doesn't downclock at idle with multiple monitors. (By design.) I have heard that if all monitors are on Displayport connections, keeping the memory speed high at idle isn't necessary, but I don't put much stock into the rumor.

 

[Zxian]

Yep, totally normal for Radeon cards. For reference, I had an EVGA 680 in my system for a while and it did downclock the memory to 150Mhz at idle. Dragging windows around on the desktop had noticable lag to it. I've got three monitors at 1200p, and that low of a clockspeed just don't cut it to drive 7MP at 60Hz.

 

[bystander36]

Yep, totally normal for Radeon cards. For reference, I had an EVGA 680 in my system for a while and it did downclock the memory to 150Mhz at idle. Dragging windows around on the desktop had noticable lag to it. I've got three monitors at 1200p, and that low of a clockspeed just don't cut it to drive 7MP at 60Hz.

I've noticed the same as far as clocks go, but they still got hotter with multiple monitors. I'm not sure what is causing the increase in temps for Nvidia cards with multiple monitors.

 

[JJ24]

Ahh okay thanks for the replies... It just seemed off to me, I don't really know why adding an extra display would jack up the temp so much. Espec when idle since we aren't doing much.

 

[2is]

It's normal and precisely why I run my 2nd monitor off my IGP. Lower temps, but more importantly, about 25 watts less power consumption at idle even after enabling the IGP.

 

[JJ24]

It's normal and precisely why I run my 2nd monitor off my IGP. Lower temps, but more importantly, about 25 watts less power consumption at idle even after enabling the IGP.

Reallly... How hard is that to arrange? my MB has Integrated intel 4000 graphics I think... may have to look into that.
It still allows for "extended" desktop I assume?

 

[ShintaiDK]

Its a known Radeon issue unfortunately. I use 2 screens and my GTX680 downclock to lowest states and no difference between1 or 2 monitors in clocks or temps.

 

[notty22]

Its a known Radeon issue unfortunately. I use 2 screens and my GTX680 downclock to lowest states and no difference between1 or 2 monitors in clocks or temps.

Same with my card. Using different resolutions,refresh rates, it works perfectly. The ability was mentioned in a driver update at one point.

 

[BrightCandle]

This wasn't the case back when the 7970's were released. The problem was there were a variety of performance problems with low clocked cards any multiple monitors, it was mostly RAM bandwidth related. They changed it somewhere around June IIRC to fix the performance problems that eyefinity users were having in Windows.

The issue is that AMD fixed the performance problem with a sizable increase in the memory speed and moderate increase in the core clock speed and that obviously pumps quite a lot more power through the GPU. The increase in power consumption is worth it compared to the alternative which is quite a poor experience in Windows.

I don't really understand why the 680 doesn't have a similar problem, I really don't get why less RAM bandwidth works on NVidia's solution and not on AMDs at the exact same resolutions. Neitherless for multiple monitors idle power consumption is quite a bit better on NVidia because of this difference.

 

[blackened23]

Its a known Radeon issue unfortunately. I use 2 screens and my GTX680 downclock to lowest states and no difference between1 or 2 monitors in clocks or temps.

That statement - no difference between 1 or 2 monitors isn't true. It's like this on all cards. With dual or triple monitors, the cards spend more time in the performance P-state. Using MSI afterburner what I find is that when I fiddle around on a single screen - this is using MSI lightning GTX 680 SLI, desktop usage is about 95% idle P state. (P0) When using dual monitors, it's twitches between middle-low-high P-state a lot when you open windows on a secondary or tertiary screen. You guys are making it sound like power consumption is unchanged from a single screen. You're not being completely forthcoming with that, because it is not true. As mentioned the power states twitch a LOT more with dual or triple screens, especially when opening any applications on the secondary or third screen - even opening a chrome window on the non primary monitor will cause the power state to twitch to middle or high performance instantly. That doesn't happen with only 1 screen connected and using adaptive power management.

Dual and triple monitors always cause more power consumption with the gpu. Now i'm not sure what the P state is on radeon cards, sounds like it just idles at the middle P state? from what the OP is stating. Nvidia cards twitch between P0-P3 when opening applications with multi monitors. For instance I just opened a new firefox window on my secondary screen and it caused the P state to jump to P3, and then levelled off at P2 after a bit. Opening a full screen chrome window on the primary screen didn't change the P state. So what's happening is the P states "twitch" alot when opening applications on the secondary-tertiary screens. Ordinarily on the primary screen, P states are unchanged. With a single screen it would stay at P0 324MHz (using adaptive power management)

 

[bystander36]

This wasn't the case back when the 7970's were released. The problem was there were a variety of performance problems with low clocked cards any multiple monitors, it was mostly RAM bandwidth related. They changed it somewhere around June IIRC to fix the performance problems that eyefinity users were having in Windows.

The issue is that AMD fixed the performance problem with a sizable increase in the memory speed and moderate increase in the core clock speed and that obviously pumps quite a lot more power through the GPU. The increase in power consumption is worth it compared to the alternative which is quite a poor experience in Windows.

I don't really understand why the 680 doesn't have a similar problem, I really don't get why less RAM bandwidth works on NVidia's solution and not on AMDs at the exact same resolutions. Neitherless for multiple monitors idle power consumption is quite a bit better on NVidia because of this difference.

Are you sure that wasn't just an error with a particular set of drivers? The 5870 and 6950 both used increased memory clock speeds with multiple monitors, except when drivers screwed up, then you'd see the 2nd monitor flickering.

 

[notty22]

That statement - no difference between 1 or 2 monitors isn't true. It's like this on all cards. With dual or triple monitors, the cards spend more time in the performance P-state. Using MSI afterburner what I find is that when I fiddle around on a single screen - this is using MSI lightning GTX 680 SLI, desktop usage is about 95% idle P state. (P0) When using dual monitors, it's twitches between middle-low-high P-state a lot when you open windows on a secondary or tertiary screen. You guys are making it sound like power consumption is unchanged from a single screen. You're not being completely forthcoming with that, because it is not true. As mentioned the power states twitch a LOT more with dual or triple screens, especially when opening any applications on the secondary or third screen - even opening a chrome window on the non primary monitor will cause the power state to twitch to middle or high performance instantly. That doesn't happen with only 1 screen connected and using adaptive power management.

Dual and triple monitors always cause more power consumption with the gpu. Now i'm not sure what the P state is on radeon cards, sounds like it just idles at the middle P state? from what the OP is stating. Nvidia cards twitch between P0-P3 when opening applications with multi monitors. For instance I just opened a new firefox window on my secondary screen and it caused the P state to jump to P3, and then levelled off at P2 after a bit. Opening a full screen chrome window on the primary screen didn't change the P state. So what's happening is the P states "twitch" alot when opening applications on the secondary-tertiary screens. Ordinarily on the primary screen, P states are unchanged. With a single screen it would stay at P0 324MHz (using adaptive power management)

How about recognizing the OP referenced GPU temps. It was heat he noticed. Nvidia's implementation causes the gpu core and memory clocks to drop to low power states constantly. If heat is not generated, it's a sign of less power being used.
So it's not the same on all cards.
That's a important difference compared to never dropping down memory clocks. Which is what causes such noticeable temp increases.

 

[BrightCandle]

This was initially a very serious bug in the early 7000 series cards drivers. The fix causes increased power consumption. The fix took about 6 months after release to arrive. This very bug is the reason I ended up switching from the AMD 7970's to my NVidia 680's, which do not suffer from it (they clock dynamically based on load, both in Windows and in games). So quite certain on the causes, I saw this first hand and raised a bug with AMD and saw the fix and its impact.

 

[jaedaliu]

One thing that wasn't mentioned that may be too basic for some, but the temperature increase is so large because your fan probably didn't change its speed.

It may be benficial to run at the higher clock. I was having problems with audio over HDMI on my video card until I changed my minimum clock speed to something faster.

 

[2is]

Reallly... How hard is that to arrange? my MB has Integrated intel 4000 graphics I think... may have to look into that.
It still allows for "extended" desktop I assume?

I simply enabled the IGP in the bios and connected my 2nd monitor to the DVI port on the motherboard and installed the proper Intel drivers for it. I have a 3770k and a 2500k that have dual monitors and using this configuration. No issues.

BTW, it's your CPU that has the HD4000 integrated into it. The motherboard simply provides the connectivity.

 

[energee]

This was initially a very serious bug in the early 7000 series cards drivers. The fix causes increased power consumption. The fix took about 6 months after release to arrive. This very bug is the reason I ended up switching from the AMD 7970's to my NVidia 680's, which do not suffer from it (they clock dynamically based on load, both in Windows and in games). So quite certain on the causes, I saw this first hand and raised a bug with AMD and saw the fix and its impact.

Yeah, I don't see enough discussion of the (very real) multi-monitor issues -- an increasingly common scenario and important consideration when choosing a card. I was going to purchase an AMD 7000 series card until recently, after seeing that between the two, only the GTX 600 cards properly downclocked during idle. The power/heat savings is non-trivial.