View Full Version : G51 - GPU automatically downclocking on battery (AC off)

08-31-2011, 07:18 PM
Hi gentlemen.
I think my problem does not just concerns G51 serie. But I didn't find any solution or even a thread talking about it yet.

Notebook : ASUS G51-Jx (model : G51JX-SX383V)
GPU : nVidia Geforce GTS 360M
Problem : when the notebook is on battery (AC unplugged), the GPU drastically and automatically downclocks itself. So, it decrease dramatically the performances ingame.
- Normal frequencies : GPU : 550 MHz / MEM : 1800 MHz = AC ON
- Limited frequencies : GPU : 405 MHz / MEM : 325 MHz = Battery ON

I've looked on my own for different ways to bypass that limitation, unsuccessfully :
- Nvidia control panel : I've tried switch to "prefer maximum performance" option, no change.
- Drivers change : I've tried the official ASUS drivers, the latest nVidia Verde, oldest nVidia ones : fail.
- PowerMizer : it's a nVidia drivers feature that limits GPU and MEM clocks frequencies on battery to enhance the autonomy. However, it can cause several issues.
I've tried 2 softwares usually recommended to disable it : nVidia PowerMizer Manager and PowerMizer Switch. They work but cant exceed the 405/325 limitation on battery.
- O/C (overclocking) : I've used MSI Afterburner. It works perfectly on AC, but doesn't work anymore on battery (neither O/C or D/C is possible).
- BIOS editor : Using NiBiTor (NVIDIA BIOS Editor) and Fermi BIOS editor. None of them can access the BIOS of this GPU.

-> It's like when on battery, 405 MHz for GPU and 325 MHz for MEM are upper limitations that cant be exceed, no matter how.
I’m not sure there’s a solution, I’m thinking this is a modded BIOS limitation.
I've asked for help on nVidia forum (http://forums.nvidia.com/index.php?showtopic=205932) and Power Mizer Manager (http://somemorebytes.com/wp/index.php/software/nvpmmanager/) one : no result.

If you have a solution or an idea, I would be very interested.
Thanks for your help.

08-31-2011, 07:52 PM
This is working as intended. The battery would die *extremely* quickly running the system at full speed, if it could run it at all. I'm not sure there is official documentation but we've speculated that the battery might not even be spec'd to safely provide that amount of current.

08-31-2011, 08:40 PM
You confirm that there is no way to bypass that ? It seems to be possible with others manufacturers laptops when nvidia powermizer is turned off. Maybe the GPU is not BIOS limited or the amount of power required can be provide by the battery, I dont' know.
Thanks for your answer.

08-31-2011, 09:08 PM
I don't own one so I've never tried and can't confirm anything. I will say that there has been discussion and people have tried and I've never heard of anyone being successful. If you do find a way to change it then make sure that you post it here for others to reference.

08-31-2011, 09:24 PM
Ok I will. I'm still looking on my own.