GPU downclocks to 600 MHz due to "power limit", doesn't even reach the power limit.

Hi!

So I have a very, very strange problem. When I play certain games my Nvidia 750m downclocks to about 600 MHz which (of course) gives me very bad performance. According to GPU-Z the PerfCap reason is power limit. So for some reason my GPU thinks it is drawing too much power and therefore it downclocks itself.

The weird thing is this only happens with certain games (Oxenfree, LIMBO) but not other games like Portal 2, A Story about my uncle or even stress tests like Furmark. When I play Portal 2, A story about my uncle and stress test with Furmark the GPU can manage about 1160 MHz at 100% load, but with Oxenfree it sits at about 600-650 MHz..

I know for a fact that Furmark etc uses more power than Oxenfree at 600 MHz, because when I run Furmark the fan ramps up to max and the GPU temp goes up to about 90 degrees celcius. When I play Oxenfree the fan doesn't even ramp up that much and the GPU stays at about 55 degrees celcius, so obviously it doesn't use anywhere near the same amount of power when I play Oxenfree compared to Furmark, Portal 2 etc where my GPU is at full load att max clockspeeds. So how come it limits itself to 600 MHz when I play Oxenfree and what can I do to fix this?

I have already tried to reinstall the GPU drivers. My power settings are at high performance. I've reinstalled the games that have this problem.

 

What model laptop do you have? Perhaps Optimus is set to "adaptive" to reduce power consumption when not needed. Oxenfree and other game don't look like GPU intensive games.

 

I have a HP ENVY 15 from 2013 with a i7 4702MQ and a Nvidia 750m. I know Oxenfree isn't a GPU intensive game, but with those clockspeeds I get about 18-25 fps at 1080p. I changed the power management mode in Nvidia control panel to prefer maximum performance, still have the same problem

 

What is the GPU usage? Is Oxenfree definitely set to use the NVidia GPU? On my computer Oxenfree is using the Integrated Intel GPU by default.

 

The GPU usage is 99-100% on my Nvidia card and 0% on the integrated Intel GPU. If i force it to use my integrated GPU I get even worse fps, but I still think I can get much better fps with my 750m since it's not even close to its max clockspeeds and doesn't even get hot when I play Oxenfree.

 

Oxenfree uses 100% on my 650m, but it seems smooth. On Intel I'd say it's about the same amount of smoothness. What are you using to check the frame rate?

 

It's definitely not smooth for me, at 1080p it's very choppy and there is a lot of input lag. The GPU load is at 100% but the clockspeeds are at 600-650 MHz. The fps according to FRAPS is about 18-25. According to GPU-Z the reason for the lower clockspeeds is power limit. So the GPU thinks it draws more power than it's allowed to, and therefore clocks itself down.

At 720p the GPU is at about 650-700 MHz (still limited by power according to GPU-Z) and the load is 100%. The experience is MUCH smoother, and FRAPS confirms that. (FRAPS shows 43-55 FPS).

At 480p (which of course looks like crap) i get a rock solid 60 fps and it feels completely smooth with absolutely no input lag. Now the GPU sits at 1162 MHz and the load is about 45%.

So it looks like the GPU thinks it reaches its power limit and and decides to downclock itself. Obviously it does not draw much power at 600 MHz, since the fan doesn't even ramp up and it stays at about 55 degrees celcius. When I play other games it can hold 1162 MHz at 100% load (and consume much more power).

 

Also, the reason it seems smooth for you might be because your GPU doesn't downclock itself to 600 MHz? If the clockspeeds are at max, a 650m could probably push out enough frames per second to not be noticeably laggy.
I still haven't found a solution yet Do you know anything else I can try?

 

Can you try downloading Throttlestop? Some boxes are ticked by default (probably about TDP throttling and BD Prochot), try unticking them and save. While you're at it, try undervolting the CPU and see if it's fixed.

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I already use Throttlestop, but as far as I know it's only for the CPU? My CPU is undervolted (-65 mV). The CPU is not the problem, the problem is my GPU that thinks it uses too much power, but only in certain games. Can I use Throttlestop to prevent my Nvidia GPU from powerthrottling?

 

I'm afraid it's only possible if the vBios you have allows setting the GPU frequency and voltage offsets.
The reason why I've brought throttlestop in question is because I suspected the entire package is being TDP throttled. Reducing the CPU voltage could help regulating the overall wattage for the GPU, and thus prevent it from throttling.

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Even if I (using throttlestop) underclock my CPU to 0.8 GHz, my GPU still throttles because "power limit" during those games, so that's not the problem
I've read about Kepler Bios Tweaker which lets me modify my VBIOS, do you think this might solve my problem?
I don't understand why my GPU only does this in certain games, do you have an idea on why this might be? When I think about it, I think I've only seen it doing it when I play 2D sidescrolling games (like LIMBO and Oxenfree), and not full 3D games. Is it maybe stuck in a "2D-mode" with a lower TDP throttle limit?

 

Try this: http://forum.notebookreview.com/threads/nvidia-geforce-gt-750m-throttling-fix.776503/

 

I've already read that thread and tried it, it did not work
Thanks anyway though!

 

What about this?
http://forum.notebookreview.com/threads/nvidia-gt-750m-throttle-at-80-celsius.767124/page-3

I'm seeing some good solutions here, like downgrading the Bios version (which does help in many cases where the latest release isn't stable), or playing around with TS settings.

 

I tried the last solution, my GPU still throttles due to "power limit", even at 50 degrees celcius (it starts to throttle instantly, even though my fps is stupidly low). This is not a temperature issue, and not a power limit issue since it can hold max clocks (even overclocked +135 MHz on both core and memory) running furmark. It might be a BIOS and/or VBIOS issue though. I'm thinking I might want to try to modify my VBIOS, but I still think it's super strange that it only happens with certain games while I can run at overclocked speeds at 100% load on other games.

EDIT: Someone said this: "You need an unlocked vBIOS and there is no such option for the GT750M.."
Do you know if that's true? Does that mean I can't modify my vBIOS?

 

Yeah, that confuses me as well. Could it be a specific driver issue with those games?

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Since I thought it might be an issue with 2D sidescrolling games I installed Never Alone (another 2D sidescrolling game) and in that game it could run at 1162 MHz at 100% load without throttling (and it reached about 85 degrees). So it's probably not that it thinks it's in a "2D-mode". I guess it could be a specific driver issue with those games, but I had the same problem with those games when I installed older drivers as well, and I don't think many others have the same problem?

I'll install a couple of other games and see which games are affected and which games aren't

 

I've now tried a couple of games and these are the results:
Bastion - No problem
Bioshock Infinite - No problem
CS:Source - No problem
Firewatch - No problem
Never Alone - No problem
Portal 2 - No problem
The Swapper - No problem
The vanishing of Ethan Carter - No problem
Life is strange - GPU core drops from 1162 to about 1000 MHz due to power limit, basically no problem since it's only about 15%
A story about my uncle - same as Life is Strange, about 1000 MHz
LIMBO - Throttles due to power limit
Oxenfree - Throttles like hell due to power limit, about 600 MHz

With "No problem" I mean it can run att full clock speeds (1162 MHz) at 100% load. So this problem only happens in a few games, but with Oxenfree it's just insanely slow and gives me super bad framerates even though the game doesn't look graphically demanding. I still have no idea what's causing this but I think I'll just buy the stupid game on my phone instead..
Thanks for your help!

EDIT: And I'm thinking that Life is Strange and A Story about my uncle might actually be hammering my GPU in a way that makes the GPU run into a real power limit, but the situation with Oxenfree is just strange..