GPU will not downclock on idle after adding a second monitor. Can this be fixed?

TetraNitroCubane

I currently use a single monitor on a system that employs an EVGA GTX 570 video card. I've recently wanted to expand my desktop by using a second monitor. It feels pretty nice to have the extra space, particularly while gaming.

However, a problem that I've encountered is that plugging in a second monitor causes a huge increase in heat output from my video card. Whereas with a single monitor, my GPU will idle at ~40 °C, if I plug in the second monitor the GPU temperature will rise to approximately 62 °C very quickly. Mind you, this is after thoroughly de-dusting my case, and also occurs just on the desktop, without running any applications. I usually keep my fans running at about 70% speed when the temperatures are below 70 °C, and then scale the fanspeed upward when things get hotter. 70% is already pretty loud.

A closer investigation reveals why the temperatures spike after the addition of a second monitor. With a single monitor, the GPU will automatically downclock itself while idle, or when in 2D mode. The core runs at a much lower clockspeed, and hence the temperatures are low. Plugging in the second monitor causes the clockspeed of the GPU to max out, and STAY maxed out, even when idling in 2D mode. I presume this is why the temperatures get so high so quickly, because even though the card isn't really being put to full use, it's still running at a much higher speed.

I've tried multiple driver revisions, and even tried uninstalling, cleaning, and reinstalling the latest official Nivida drivers. Nothing seems to allow for auto-downclocking on 2D mode with dual monitors. Does anyone know how to resolve this issue? I'd love to use more than a single monitor, but idling at upward of 60 °C is just off-putting, and makes me worry for the health of my system.

Draygo

When you plug in a second monitor your gpu is now doing twice the amount of work it was doing before. This may be normal and nothing to worry about. 62c is also fine.

TetraNitroCubane

Well, sure, but it's still desktop 2D stuff. It hardly uses 2% of the GPU according to the Precision tool. I can't imagine the core clock needs to be at 797 Mhz for that.

I appreciate that having two monitors will have an impact on heat and performance, but it's pretty clear this heat output is just because of a failure to downclock. If I set my core clocks manually to 797 with one monitor, the temps raise from ~40 to ~60. If I could downclock to the 2D clockspeeds with two monitors, I'm pretty sure the temps would reduce to the roughly 40 range.

Ego

Try a manual clock tool to lower it. You'd be surprised at how many GPUs outright crash if you underclock them to a decent degree while a second display is plugged in.

Knight_

TetraNitroCubane wrote:

I currently use a single monitor on a system that employs an EVGA GTX 570 video card. I've recently wanted to expand my desktop by using a second monitor. It feels pretty nice to have the extra space, particularly while gaming.

However, a problem that I've encountered is that plugging in a second monitor causes a huge increase in heat output from my video card. Whereas with a single monitor, my GPU will idle at ~40 °C, if I plug in the second monitor the GPU temperature will rise to approximately 62 °C very quickly. Mind you, this is after thoroughly de-dusting my case, and also occurs just on the desktop, without running any applications. I usually keep my fans running at about 70% speed when the temperatures are below 70 °C, and then scale the fanspeed upward when things get hotter. 70% is already pretty loud.

A closer investigation reveals why the temperatures spike after the addition of a second monitor. With a single monitor, the GPU will automatically downclock itself while idle, or when in 2D mode. The core runs at a much lower clockspeed, and hence the temperatures are low. Plugging in the second monitor causes the clockspeed of the GPU to max out, and STAY maxed out, even when idling in 2D mode. I presume this is why the temperatures get so high so quickly, because even though the card isn't really being put to full use, it's still running at a much higher speed.

I've tried multiple driver revisions, and even tried uninstalling, cleaning, and reinstalling the latest official Nivida drivers. Nothing seems to allow for auto-downclocking on 2D mode with dual monitors. Does anyone know how to resolve this issue? I'd love to use more than a single monitor, but idling at upward of 60 °C is just off-putting, and makes me worry for the health of my system.

Technically, this is intended functionality, as Nvidia has the cards do this on purpose. However, there is a way to force the voltage reduction on 5xx series and below cards. http://www.overclock.net/t/964370/fix-info-dual-monitor-downclocking-fix-for-nvidia-cards

That said, I ran a GTX 560 Ti at full power for 2 years because I never bothered to mess with Nvidia inspector and never had any problems with it. Used to idle at 70 and be under load at 90+

TehSloth

Yeah, it sucks but unfortunately they design the cards to always be in 3d mode when they are using multiple monitors. You may be able to use EVGA's Precision software to force it into the 2d profile, but I'm not sure it'll work. I've had much more luck fiddling with things using precision than I have by doing it with the tweak settings in the actual nvidia drivers. I've also heard it'll properly use the correct profile if you only use one monitor per card by way of sli, but that's hardly a real solution since you'll still have similar heat and power consumption with two nearly idling cards.

emp123

I also have a 570 and Im also running dual monitors and from what Ive read the only way to get the card to clock down is to either shut off the second monitor (by turning it off in the preferences, theres an option to not have anything display on the second monitor) or to buy another 570 and SLI them (I think the second monitor has to be plugged into the second card).

Im a little surprised at your temperatures though, my card idles at around 33c with one monitor and around 42c with 2 (I have a non-reference EVGA cooler though), but I think the card is rated to be fine as long as its under 100c.

TetraNitroCubane

Thanks, everyone. I hadn't any idea that there were technical reasons for the clocking behavior when two monitors were employed. I had assumed it was some variety of driver glitch, and that it might be fixable with a few tweaks. If there's a legitimate reason that Nivida have put this behavior into the card, then I'm sure it's probably best that I don't poke it too severely. I'll just learn to unplug the second monitor when it's not in use.

@emp123: The temperatures on this card have always surprised me, but I admit that I'm using stock cooling. I actually removed the card from my case yesterday and gave it a thorough de-dusting, but the temperatuers only came down about 4 °C. But it does stay under 100 °C even under load, so I might just chalk up the high idle temp to it being summer, I suppose.