Centrino undervolting...

sledgy · Jan 2006

I know alot of people on these boards (like myself) are going the laptop route, or at least have them for useful stuff like painting or modelling on the road (playing bf2). I find Intel speedstep technology very irritating when I'm in the middle of combat and suddenly the CPU jumps down to 600Mhz and I'm in a chopper, then I'm suddenly embedded in the ground.

http://www.rojakpot.com/showarticle.aspx?artno=177&pgno=0

This worked very well for my centrino notebook. Basically you undervolt your CPU. Intel will volt a CPU at a setting which all CPUs of that class will without a doubt operate reliably at. The reality is however that not all CPUs are the same and some can take much lower voltage and be able to operate flawlessly at the same clock speed under heavy load. I was able to undervolt my 1.6GHz centrino from 1.34 down to .94 volts so far (without a crash yet under the prime95 torture test) which translated into about 19C less in temp, not to mention the additional battery life. My clockspeed never goes down and the fan doesn't need to turn on. Hopefully this proves useful to some other polycounters. Now to just find a centrino overclocker...

gauss · Jan 2006

overclocking - old and cliche, undervolting is the new hip!

very interesting stuff... i don't use my laptop for gaming but this is a very interesting issue.

Soccerman18 · Jan 2006

Gotta be careful with that though. There is voltage range on transistors as to what voltage is considered a 0 or a 1, which is why your computer still works at a lower voltage level. For example, basic 5V CMOS will see a 0 anywhere from 0V to 1.5V and a 1 from 3.5 to 5V. The problem is the inbetween voltages. As a transistor switches from a 0 to 1 or 1 to 0 it hits a point where the voltage level is not at either a 1 or 0 and at that point the transistor becomes basically a short ciruit.

Most transistors I've seen run at 30% and 70%, so .3*5=1.5V for 0 and .7*5=3.5V for 1. In your case, .7*1.34=.938V which you're very close to. I'd suggest bumping it up a bit just to be safe.

Downsizer · Jan 2006

He's right. If you undervolt something, and say...the power fluctuates in the house and causes it to drop, you'll short everything. Notebook architecture has the failsafe of a battery passthrough, if you trust that, by all means. Buying another battery is a much safer solution.

hawken · Jan 2006

sounds interesting. My laptop is a beast and sounds like a vacum cleaner, even if it's doing nothing.

poopinmymouth · Jan 2006

My laptop is undervolted, I use Rightmark to manage mine. I get a ton more battery life per charge, and the fan speeds up less (though I could care less about the sound of my machine)

sledgy · Jan 2006

Found a cool overclocker for Centrino too...

http://www.rojakpot.com/showarticle.aspx?artno=177&pgno=1

I got the 845 version to work with mine. It forces a clock up of the AGP & PCI buses along with the FSB but I was able to squeeze 1817Mhz out a 1600Mhz chip running the torture test for 12 hours solid at <60C, 1.004V. None too shabby! THEN I clocked my GPU up from 337Mhz to 400Mhz and the memory from 250Mhz to 282 and I got a woody. That's a very nice performance increase on this little machine for free.

Downsizer · Jan 2006

You do know overclocking will basically halve the life span of the system right? Have fun, but may i suggest you run a processor check to see if there are any calculation errors at that speed increase?

sledgy · Jan 2006

When the life of a typical gamers' CPU in years can be counted on one hand, I don't think that's really a cause for concern. But the whole point of undervolting is to get the CPU running cool. Mine just happens to run undervolted AND overclocked at a middling 60C with no errors (follow the link for the Prime95 torture test) - it's just chip optimization on a per-case basis, nothing extreme.

Centrino undervolting...

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