GPU undervolting -worth doing?

First of all, i havent seen many people talking about this subject. I have a 9800M gs with quite high temperature(86 C under heavy load), i lowered the voltage for 3D gaming from 1.05 V to 1.00 V, but i dont see much of a difference, the load temperature ran only about 1-2C cooler. Now i am doubtful whether its worth the hassle.

Anyoneelse tried to undervolt their GPUs? How is your result in decreasing the temperature of the GPU?

 

you can undervolt the GPU? what software did you use.

 

Just now, I wanted to undervolt my Nvidia Geforce 9500M GS.
However, when I was editing the Nibitor, it only allow me to lower 0.05V which is damn little. So, I give up and stay with original BIOS setting.
If you already flashed it and it is stable, leave it like that. It is harmless. Don't flash and flash and flash. Later, a bad flash K.O. the GPU.

 

I would say it's worth it (even for 1C cooler).

BTW have you tried changing the thermal paste?

 

I undervolted my gpu from 1,05V to 0,89V and lost about 15 degrees. So yes, definitely worth it. It changed my life ;-). From 92°C i went to 75°C. And i can still overclock up to 25%.

 

The Nibitor shows me the lowest voltage i can go is 0.900V, the default one is at 1.05V, however i am afraid of keeping flashing my GPU to find out the lowest stable voltage as it's much riskier than OCing your GPU with software, one bad flash, then you might be done, just like what u said.

I think i can lower my voltage a bit further, but i am kinda scared to keep flashing my GPU. I didnt try changing/reapplying the thermal paste as my warranty hasnt expired.

Dude, u are very lucky to be able to undervolt that much, i envy you,lol. But doesnt undervolting reduce the GPU's potential to OC? how could u still OC by 25% with that massive undervolting?

 

1- Yes you can undervolt with any BIOS editing software

2- No, neither UVing or flashing are dangerous if done right. (keeping backup BIOS's, being prepared to blindflash). Ive flashed my vBIOS 20+ times, NEVER had a bad flash.

3- Yes undervotling can reduce your OCing ability, but it also can improve it. Most of the time Overclocks are limited by excess heat not insufficient voltage.

 

Agreed with classic77

Futhermore ... while undervolting DOES reduce OC-ing ability, I hardly think you would have significant gains going over 25% or 30% overclock to begin with because people have even reported decreased performance with much higher clocks.

OC-ing will increase the heat produced by the card (even with the undervolt in question), but it will still be lower compared to what the non-undervolted/oc-ed card will produce.

 

Yes you're totally right, OCing ability is reduced but in the meantime it is more stable than before due to less heat. So it's worth it. I'm 75°C on stock clocks and 78°C with 20% OCing so it's more stable than before. I used to reach 90+++ before undervolting with same OCing (20%).

That's just luck gpu can handle it that's all. From 500/1250/800, the max i can go undervolted is 620/1550/800. The memory can even handle more (about 900-950 mhz) but that's not stable in every game only in 3dmark bench so i don't touch it now. 600/1500/800 are my usual clocks (20% on core and shaders). Good compromise.

BTW i envy your GPU

Is your cpu undervolted too ? If not do it the benefits of undervolting the gpu will be more obvious if cpu and gpu are cooled by the same only fan in your notebook.

 

hey guys, is there any guide which explains how to undervolt gpu using nibitor? thanks..

 

well i googled a bit. apparently nibitor is a very dangerous app if you dont know what you are doing. it flashes a new bios over the original one.

 

No it doesn´t. Nibitor only reads your bios and allows you to modify it, but the changes done to it are saved to a new bios (.rom or .bin). After that, to flash the new bios you have to use nvflash.

 

I am still tempted to further undervolt the 9800M gs because i only lowered the default voltage from 1.05v to 1.00v in the previous flash, but the problem is that the only choice left for me is 0.90v, Nibitor only allows me to undervolt either to 1.00v or 0.90v, I don't think 0.90v is sufficient for heavy 3D gaming as the default voltage for all 2D/light 3D uses is at 0.90v too. Damn I wish Nibitor gives me an option to lower the voltage to 0.95v.

Anyway, if i did a flash that couldnt provide enough voltage to the GPU, the worst i get is a BSOD, right? I can always flash back to the old bios if thats the case.

 

Yes go ahead try 0,90 V there no risk in undervolting you will just BSOD in the worst case. As you said you will be able to flash back. Frankly when i went from 1,05V to 0,89V i thought like you but it worked. And i bet it will work for you too. At least at stock clocks. Of course it will lower OCing ability (if you OC ???) but maybe not completely like me. Let me know how it worked for you

You may think that your gpu, since it's more powerful than mine, could not handle 0,90V. But your Gpu use more amperage (current) than mine anyway. Voltage is just a part of the story.

 

Those are good temps, Kallogan.

Make sure you always stress test the GPU thoroughly before sending it out to the games.

 

I played undervolted for months and tried it on many different games it works perfectly so don't worry And i'm not the only one, my colleagues on the Acer 5930G thread can confirm cause they're on 0,89V too Performances are exactly the same.

 

I wasn't worrying, nor was I address you individually. But that's good to hear that your GPU works fine on your games.

 

Errrr too bad. On the bright side, you're aware now

 

Aware of what?

 

Heres the proper guide for notebooks:

http://forum.notebookreview.com/showthread.php?t=269020

 

A little update on my UVing experience: I lowered the voltage for Extra to 0.90v from 1.05v and did the flash successfully, did a few futuremark/game tests upon restart, it ran fine, no BSOD or whatever. However the temperature drop isnt significant at all, the max load temperature decreased like 3-4 C. Needless to say, i am very dissapointed of the result. Now i am debating whether UVing the GPU is worth the risk and hassle it involved, and not to mention it has negative effect on your OC ability too.

Apparently UVing CPU gives me far better result in decreasing the temperature,
I have read people with 9600GT and 4650 experienced 15 C drop of GPU temperature after UVing, maybe it works best for the mid range card and its not very efficient for cards with high TDP like 9800M since they already emit a large amount of heat?

 

@lidowxx

Thats a decent drop for load temps. Again, the drops will probably be different between all GPUs. A drop of 0.05v for my GTX 260M dropped load temps by around 5-8C

 

i cant get NiBiTor.v5.2 to work on my 9600gt in win7 64bit
it says "cant start driver 1275"
how can i get it to read the bios on the card?

 

You need to extract the bios file first using GPUz, then rename the file extension to .rom, load Nbitor, open the bios file you just saved.