GTX 460 does not dynamically undervolt with dual monitors **solved**

[SickBeast]

I just wanted to share this. I recently hooked up a 2nd monitor to my GTX 460 and I noticed that my idle temps were way up (45C vs. 25C before). At first I thought MSI Afterburner was the culprit, so I flashed my BIOS with the overclocked speeds I wanted. The problem persisted. I did some digging online, and it turns out that enabling two monitors on the GTX 460 stops it from lowering the voltage during idle.

This is a big deal IMO. It's going to kill the cards faster and use up way more electricity.

Perhaps it's a bug and nVidia will fix it.

*edit* solved!!!

notty22 came up with a solution in post #26 of this thread. Essentially you use nVidia inspector, right click on the "overclocking" button, choose the multi monitor power saver option, and it works like a charm.

 

[happy medium]

Both AMD and Nvidia cards have been this way for months, they are not gonna change it anytime soon as far as I know.

Dual monitors= raise clocks= raise temps

 

[darkswordsman17]

I assume this is the same issue that's been covered quite a bit already on here, which is that with Vista and Win7 Microsoft changed the GUI such that it is hardware accelerated which causes GPUs to not run at typical idle 2D speeds. You can disable the extra effects I believe. I believe it also really only happens if the two monitors are different resolution, although with the new programs (browsers like IE9 and Firefox4) being hardware accelerated as well I'm curious if things aren't going to get to where GPUs are always under some load.

I think that there's going to have to be some changes in the drivers and/or Windows handling of GPUs in order to keep things reasonable. At minimum I think nvidia and AMD need to look at clock speeds and general performance so that they can find optimal settings to keep power consumption low while offering good performance. Or maybe implement some different power gating techniques. Hopefully they'll come up with something, like they did for stuff like Furmark. I think Microsoft should also look into this (for instance the hardware acceleration actually causes some fonts to be blurry which, right now the only option to fix is to disable the acceleration).

Right now the best solution is to use multiple GPUs for multiple monitors, it keeps the idle states in check and should offer the best performance. Depending on your uses, just an integrated GPU should work quite well.

 

[Vesku]

Simplest thing to check, are both monitors set at the same resolution? That can cause higher than necessary low power settings. I believe the lowest dual monitor low power clock for nVidia cards is 450MHz but that could just be with my GT 220 and GTS 450.

You should search for previous threads for this problem, I believe Idontcare had a thread like this that listed a lot of fixes and tweaks.

 

[Grooveriding]

This is how it is, unless the monitors are running identical resolution and refresh rate.

I find the problem is worse on nvidia hardware as they run the core at full load voltage and the full memory clock speed with the core at 75% of load speed. So it basically runs pretty hot, on a 480 you get idle temps of 70C

I don't actually use more than one monitor at a time so what I do is disable the second monitor (an HDTV) and change to extended mode when I want to use that screen.

 

[SickBeast]

The best workaround I've found is to flash the card with the overclocked speeds I want, and then use MSI Afterburner to underclock the card whenever I have both screens enabled. I tried using the 2d/3d profiles but it did not work.

Anyhow, it's quick enough to hit "reset" in Afterburner whenever I run a game.

This issue seems dumb to me. If it's stable for me at the lower voltage, why on earth did nVidia and AMD do this? There must be a reason.

 

[SickBeast]

Simplest thing to check, are both monitors set at the same resolution? That can cause higher than necessary low power settings. I believe the lowest dual monitor low power clock for nVidia cards is 450MHz but that could just be with my GT 220 and GTS 450.

You should search for previous threads for this problem, I believe Idontcare had a thread like this that listed a lot of fixes and tweaks.

Yeah they're at different resolutions. They are downclocking to 450mhz on the core, however it's leaving my voltage at 1.2v (my overclocked voltage) in 2d mode, which is causing the card to idle 20C hotter than with one monitor turned on.

I found the thread you're talking about by Idontcare, and he had the opposite problem that I'm having. His card would stay in the low power mode even during gaming.

Thanks everyone for the input. :thumbsup::thumbsup:

 

[SickBeast]

I assume this is the same issue that's been covered quite a bit already on here, which is that with Vista and Win7 Microsoft changed the GUI such that it is hardware accelerated which causes GPUs to not run at typical idle 2D speeds. You can disable the extra effects I believe.

I disabled the effects and the problem persists, plus it makes my computer ugly. D:

 

[Grooveriding]

The best workaround I've found is to flash the card with the overclocked speeds I want, and then use MSI Afterburner to underclock the card whenever I have both screens enabled. I tried using the 2d/3d profiles but it did not work.

Anyhow, it's quick enough to hit "reset" in Afterburner whenever I run a game.

This issue seems dumb to me. If it's stable for me at the lower voltage, why on earth did nVidia and AMD do this? There must be a reason.

I've read some information that says it's related to memory speed. When the card is downclocked and you run two monitors you get flickering on one of the screens.

On my 5870s I experienced the flickering, then AMD released a driver update and the cards would run full memory speed and this fixed the issue. It is probably the same problem with nvidia, their cards run full memory speed and load voltage and a core clock bump when you run two monitors or more.

 

[Vesku]

How are you setting your overclock voltage? If it's MSI Afterburner or similar, then having another profile seems the easiest way to lower non-gaming temps.

 

[SickBeast]

How are you setting your overclock voltage? If it's MSI Afterburner or similar, then having another profile seems the easiest way to lower non-gaming temps.

I tried that and it didn't work. Perhaps I did something wrong. *shrug*

You don't need to do anything by default anyways. The card clocks down to something like 100mhz when idle, so long as you only have one display hooked up.

 

[darkswordsman17]

I disabled the effects and the problem persists, plus it makes my computer ugly. D:

Yeah, disabling the acceleration isn't really much of a fix. Sounds like there's a hangup either with your MSI program or the drivers (or possibly both trying to do something, like the MSI keep settings while the drivers are trying to downclock/drop voltage).

 

[Idontcare]

Beast your observation runs counter to mine.

GTX460 here with dual-screen, idle temps are 26-30C, core clocks drop to 51MHz, mem clock to 135MHz, shader clock to 101MHz, Vcc is at 900mV (vs 975mV stock).

MSI cyclone GTX460, stock overclock, whatever BIOS came with the card back in Nov timeframe, driver is 267.24, Win7 Ult x64.

 

[SickBeast]

Hmm. Perhaps the 270 drivers are the culprit then. I'm on 270.61.

Thanks for the info, Idontcare.

 

[SickBeast]

Actually, Idontcare, are both of your displays running at the same resolution?

 

[Idontcare]

Actually, Idontcare, are both of your displays running at the same resolution?

Yes. 1920x1200 DELL 2407's

Is that the key difference?

 

[SickBeast]

Yes. 1920x1200 DELL 2407's

Is that the key difference?

That's what people are saying. I've got a 2407 as well, but my secondary screen is a 1280x1024 analog LCD.

The thing is, even if I set both displays to 1280x1024, the problem persists.

I don't like downgrading my drivers but I might do it to see if it helps.

Thanks for your help, everyone.

 

[notty22]

Same resolution/60hz allows the memory to downclock as well at the core. I don't have 2 monitors right now , but I did. My experience (2 different resolutions) was the core did still down volt from .978 stock, and the gpu core also down clocked, but the memory did not.
As far as the op's temps. 1.2v is pretty high for gf 114, and contributing to your current temperatures also.
I would set-up your system so your 2d voltage is at a stock setting. 1.0 V or there abouts.

 

[BFG10K]

From my understanding this is related to GDDR5 having to be clocked high to stop the displays from flickering, so it’s a limitation with both vendors.

 

[SickBeast]

Same resolution/60hz allows the memory to downclock as well at the core. I don't have 2 monitors right now , but I did. My experience (2 different resolutions) was the core did still down volt from .978 stock, and the gpu core also down clocked, but the memory did not.
As far as the op's temps. 1.2v is pretty high for gf 114, and contributing to your current temperatures also.
I would set-up your system so your 2d voltage is at a stock setting. 1.0 V or there abouts.

My experience is the same as yours, except my voltage only goes down if I only have one monitor hooked up.

I realize my voltage is high, but I run the card at 950mhz on the core and I enjoy the performance it's giving me.

My 2d voltage is set to a stock setting (0.875v).

 

[SickBeast]

From my understanding this is related to GDDR5 having to be clocked high to stop the displays from flickering, so it’s a limitation with both vendors.

I'm fine with the memory staying at 2100mhz. I just want the core to fully downclock and undervolt when I have two monitors hooked up.

 

[96Firebird]

Do you use both displays all the time? I do what Grooveriding said, only enabling the second display when I want to use it. It is my HDTV as well...

 

[F1shF4t]

My 5870 has the same issue. It stays in low power 3D clocks instead of 2D when using two monitors. Not as bad but still makes a 15-20C idle temp difference. Now I just use the onboard card to drive the second monitor.

Might be worth getting a cheapo passive nvidia card for the second monitor or use onboard if you have it.

 

[SickBeast]

My 5870 has the same issue. It stays in low power 3D clocks instead of 2D when using two monitors. Not as bad but still makes a 15-20C idle temp difference. Now I just use the onboard card to drive the second monitor.

Might be worth getting a cheapo passive nvidia card for the second monitor or use onboard if you have it.

Yeah, that's the thing, I don't have onboard graphics and I don't think it would be worth buying a card to save a few cents on electricity.

I'm wondering, if I have two cards hooked up in SLI, can each card output to one display, thus alleviating this problem? I've been thinking about getting another GTX 460 anyways.

 

[XLer8]

Heres something odd... My GTX 570 does this. Even if I use it with a 8800 gts for second monitor. But when I do a older 7600gs for the second monitor it drops down at normal. I think its partially due to driver, it doing this. Monitors are dif res too.