Undervolting Question For 9400

I am a noob to undervolting, so expert advice would b really helpful.
I am currently running at 12* 1.012V and system is very stable.
According to physics when u undervolt the current will increase and the overall Watts comsuption might end up being the same or even increase.
So just wondering, will the extra ampre damage the cpu in anyway? cuz its brand new laptop, and how can u actually check for power compustion?
Thanks 4 the help.

 

Also how come I cant run two prime95 at the same time?
is there anything specific u have 2 do?

 

you need to save prime95 in two different folders. as far as know, the only problem that can arise from undervolting is instability to your cpu not having enough voltage to run.

 

so in this case v decrease A stay the same and p (watts) decrease = longer battery?
And no negative side effects if everything is stable?

 

Since this is done on the CPU, can we do it to the GPU as well?
If so, what bios should i flash, and what settings to use.

 

Another thing so if I undervolt from 1.212 to 1 then I am saving about 6watts is that how you calculate it? or r there any other factors to b considered.

 

Anyone pls help

 

OK. Here's simple resistive rules.

P (power) = E (volts) * I (amps)
E/I = R (resistance)

The T7200 has a TDP of 34W and a core voltage of 1.3 volts max.

34w=1.3 * I
34/1.3 = I
I = 26.15A

1.3/26.15 = R
R = .05 Ohms

Now, say you drop voltage to 1.1, what will that do to the amperage?

I = 1.1/.05
I = 22A

And what does that do to watts consumed?

1.1 * 22 = P
P = 24.2W

But a processor is a lot more than just a resistive load.

 

So in this case r u saying that the resistance will stay the same? Shouldn't derease according to physiscs less heat = less resistance? I used to b good in physics, returned it all to the teacher now, lol.
And can u undervolt the GPU too?
Can anyone confirm with scienctific proof that undervolt will not damage the CPU, sory, I am just picky about those stuff. Want to actually know what I am doing.

 

Like I said. A CPU is lot more than just a resistive load. That was just to show that when you decrease voltage, amperage also decreases, with the same load applied.

I don't see why you can't undervolt the GPU also. But don't ask me how.

Undervolting won't damage anything, other than your data if the processor becomes erratic and corrupts information because of not having enough power to operate properly.

 

underclocking your cpu doesn't necessarily yield better battery life. i did awhile back for an ultraportable i reviewed and it didn't improve the battery life at all. it did help significantly with heat and fan noise though. i'm not quite sure where you got your original statement....care to explain?

 

While undervolting won't damage your system it can cause some abnormal behaviour. Heat will obviously be reduced, and thus fan speeds, so you might get a system which is a little more quiet. But I am not sure where you've got the idea that undervolting will increase performance...
In the good old days, before CPU manufacturers locked the multipliers (maybe AMD still allows lowring multiplier on their premium cpu's) you could have lowered it and up the voltage to overclock the cpu, perhaps that's what you're reffering to?
Otherwise I'm not sure I understand how you mean undervolting helps in terms of performance..

 

I seen from other posts that from under volting u usually get an extra 10-30 minute battery life if u r always running on full speed. As you see from the tread We tried to find out how much power can u actually save as that is the laws of physics, though i am not too good at it now. As for performance, I never remembered saying anything about that, or underclocking for that matter. Sorry I misguided Balistic. And back to ejl, when u undervolted, how much did u do, what test did u run and r there any measurements u took. Volt Resistance, ampere, etc? I donnt understand y when u under volt the watts consumed does not decrease. As said by WackyT, when u under volt v decrease i decrease p should also decrease. (P=VI).

 

As to test if the system is stable, PI to 16mi on one cpu and prime95 torture on another should be a good indictor right?