Undervolting Laptops?

[firewolfsm]

I'm surprised undervolting laptops and netbooks isn't more widely done as I'm sure the benefits would be worth the effort. Mobile processors are probably run closer to their optimal voltages to save power but even these must have headroom. My Q6600 was still stable at 1.125 volts at stock speeds and I actually noticed lower heat output by several degrees after I did that. It could probably improve battery life dramatically.

So...I guess my question is, as I can't find much info online, is there a reliable way to undervolt Centrino notebooks (ram, cput or chipset)? Either through hardware mods or software. Most BIOS setups don't allow for these changes but the hardware must be capable of it.

 

[corkyg]

If one runs almost always on A/C, there really is not much to be gained. But - if you really have to be on battery power, it may be worth it.

under

 

[fffblackmage]

Originally posted by: corkyg
If one runs almost always on A/C, there really is not much to be gained. But - if you really have to be on battery power, it may be worth it.

under

You mean when the laptop is plugged to the wall outlet? You can still get better temps using lower voltages.

That link looks interesting, I'll probably try that sometime....

 

[corkyg]

Originally posted by: fffblackmage You mean when the laptop is plugged to the wall outlet? You can still get better temps using lower voltages. That link looks interesting, I'll probably try that sometime....

Yes - plugged in to a wall outlet. Lower temps are irrelevent if the standard ones are within limits. All you do is sacrifice performance for a feel good condition. Yeah - I can get much better gas mileage at 55 mph, but, I prefer to go a little faster.

 

[fffblackmage]

Originally posted by: corkyg

Originally posted by: fffblackmage You mean when the laptop is plugged to the wall outlet? You can still get better temps using lower voltages. That link looks interesting, I'll probably try that sometime....

Yes - plugged in to a wall outlet. Lower temps are irrelevent if the standard ones are within limits. All you do is sacrifice performance for a feel good condition. Yeah - I can get much better gas mileage at 55 mph, but, I prefer to go a little faster.

When you lower voltage, you do not necessarily lower frequency (I mean, you could to lower voltages even further), but if frequency isn't changed that doesn't equate to lower performance.

Lower temps are not necessarily relevant like you said as long as they are within normal limits, but it could also mean lower fan speed, and, thus, less noise.

But like you said, it's just extending the battery time longer that is really the biggest gain.

 

[ther00kie16]

This used to be the first link that came up when googling for this topic, not it's like the 5th.

 

[firewolfsm]

I was thinking more along the lines of a hardware mod, akin to overvolting techniques so many use, but this seems to work too.

 

[JeffreyLebowski]

I used the RM-clock untility on my notebook and I got better battery life by cranking the voltages all the way down.
An annoyance though was that even though the temps reported lower the fan would kick on earlier and run non stop. I had to stop using it because the fan noise was to much.

 

[aceO07]

I use NHC on my WindowsXP laptop and RM-Clock on my Vista laptop. On the Vista laptop, it probably lowers the max temp by 10c. On the WindowsXP laptop, I like it to maximize my battery life. I think NHC is supposed to have another version out eventually but it's been really really slow to release. I actually prefer NHC since it's easier to use and the interface is nicer, but it doesn't support the newer processors and Vista.

Originally posted by: firewolfsm
So...I guess my question is, as I can't find much info online, is there a reliable way to undervolt Centrino notebooks (ram, cput or chipset)? Either through hardware mods or software. Most BIOS setups don't allow for these changes but the hardware must be capable of it.

NHC should be able to do it (also RM-Clock). I think my WindowsXP laptop is a centrino.

 

[MrX8503]

Lowering voltages is lowering the volts at which the CPU frequency operates at.

Lowering voltages != Lowering CPU frequency != Loss performance.

Low Volts = Better battery life = Same performance = Cooler laptop.

 

[herm0016]

i use nhc and love it. i can still get 4 to 5 hours out of my 5 year old 600m with light to moderate use while undervolted.