Undervolting Your CPU ? This is SPARTAAA!!!

26-04-09

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Undervolting Your CPU ? This is SPARTAAA!!!

Undervolting Your CPU?
This is SPARTAAA!!!

Ok. This is not unfortunately titled.
You...

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Last edited by vijayninel; 20-06-09 at 06:08 PM.

#15

By vijayninel 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

I really need a graphic card that has spartan consumption of energy...

#16

By Free Radical 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

Finally a little birdy chirped

#17

By BLuEBLOODED 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

Nice discussion there...

And nice tutorial put as well...

#18

By Free Radical 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

ty. cmos circuits rely on the Mosfet formula, though still, heat produced is proportional to the square of voltage. With future dye shrinks, I bet more energy efficient processors will start appearing, though I hate the fact cpu manufacturers are pushing multiple core processors and going for the monolithic design (like gpus) rather than thermal efficiency

#19

By JD666 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

good going dude!! though you would save about 5-20 watts of power per hour.. its still a saving none the less, and a cooler running rig also.. giving me ideas, when i undervolted and underclocked to 1.8ghz at 0.98 volts. The CPU would further scale down to 1.2ghz after EIST! temps hardly mattered... it was like the cooler was not even needed!!

#20

By Free Radical 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

My stupid mobo doesn't do P/T state transitions at all. Prolly just a quirk with my mobo as it should according to Asus and I don't wanna underclock at all.

#21

By sahilm 28-04-09

Re: Undervolting? This is SPARTAAA!!!

Originally Posted by Free Radical

lol.

ohms' law
V=IR

Joule's law
H=I^2Rt=VIt=(V^2)t/R

A semiconductor isn't a purely ohmic material. I don't think Joule's law can be applied empirically.

#22

By stonedsurd 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

But it gives a basic idea - which is the aim of the article, after all

#23

By sahilm 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

Why can't I edit the above post? You already mentioned the above.

#24

By Free Radical 28-04-09

Re: Undervolting? This is SPARTAAA!!!

Originally Posted by sahilm

A semiconductor isn't a purely ohmic material. I don't think Joule's law can be applied empirically.

keyword is proportional.

#25

By Free Radical 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

temps are still proportional to vcore voltage squared, be it ohmic or not

#26

By Rockfella 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

Cool, FR can i have that pic u have in the background?

#27

By sahilm 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

Originally Posted by Free Radical

temps are still proportional to vcore voltage squared, be it ohmic or not

That is not entirely correct. Temperature is proportional to (vcore)^2 only within a certain range. Boundary conditions are different. Below a certain leakage current, temperature will remain constant. Beyond the threshold current(voltage), the p-n junctions will break down and cause an avalanche. Causing a minor spike in temperature and in effect killing the CPU.

Obviously my above points are academic. It's not possible to set your current below the threshold on any motherboard. The computer will refuse to boot. You can however set an absurdly high voltage and avalanche your processor. That's why extreme overclocking even with extreme cooling is dangerous. The processor dies of voltage(zener breakdown) rather than excessive temperature.

Enough of pseudo scientific talk from my side. Good article. Reps on the way.

Last edited by vijayninel; 28-04-09 at 10:55 PM.. Reason: Undesireable word replaced

#28

By ManISinJpr ♦ 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

FR again a fantastic tute so what's next?
Repped you...

#29

By Free Radical 28-04-09

Re: Undervolting Your CPU ? This is SPARTAAA!!!

Originally Posted by sahilm

That is not entirely correct. Temperature is proportional to (vcore)^2 only within a certain range. Boundary conditions are different. Below a certain leakage current, temperature will remain constant. Beyond the threshold current(voltage), the p-n junctions will break down and cause an avalanche. Causing a minor spike in temperature and in effect killing the CPU.

Obviously my above points are academic. It's not possible to set your current below the threshold on any motherboard. The computer will refuse to boot. You can however set an absurdly high voltage and avalanche your processor. That's why extreme overclocking even with extreme cooling is dangerous. The processor dies of voltage(zener breakdown) rather than excessive temperature.

Enough of pseudo scientific bakchodi from my side. Good article. Reps on the way. .

I knew you'd mention that

And your comments are very welcome

Its not pseudoscientific. But rather that is due to overvolting as you rightly mentioned. Infact that is the precise reason why highly oced proccies die sooner than stock ones and why cpu "burn in" is hogwash.
http://www.xtremesystems.org/forums/showthread.php?t=54382We all studied Zener breakdown in 12th didn't we

besides, overvolting stresses your psu's switching fets, diodes and inductors causing more thermal dissipation.

undervolting helps both your processor and your psu

though of course we love to oc don't we

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