Intel rep actually reveals safe voltage for Haswell

Hey just thought I would share this.

http://www.youtube.com/watch?feature=player_embedded&v=ylNT1Co-Q6k

around 20 minutes 30 seconds is the relevant part.

anyways I just thought it was interesting that the rep actually made a voltage recommendation as Intel's official position on safe over voltage amount is usualy "no comment"

for those of you who don't want to watch the vid basically a rep from Intel talking to newegg TV flat out states that your should not exceed your cpu's base voltage by more than 10% for Haswell. he also admits that sandy bridge could handle higher percentages though he is not as direct about that.

Greetings

kinjo said:

anyways I just thought it was interesting that the rep actually made a voltage recommendation as Intel's official position on safe over voltage amount is usualy "no comment"

Click to expand...

WTF??? I don't know why this is so as they publish the actual figures on their website for anyone to read, an example will suffice so lets take the old core i7-9xx cpu's.

You just have to look up the processor datasheet (this will also be available for Haswell once its officially released).

The page concerned is here and the direct link to the PDF is here.

You read it in the following fashion as there are two limits we are interested in the maximums only (as the minimums are not important to us).

First is the ABSOLUTE MAXIMUM on page 22 Table 2-6 which quotes a maximum of (Vcc) 1.55 Volts so if you exceed this limit you will DAMAGE YOUR CPU.

Second is the FUNCTIONAL MAXIMUM on page 23 Table 2-7 which quotes a maximum of (VID) 1.375 Volts.

The explanation for operating between these two limits is given at the bottom of page 21 and states

***********************************************************************************
Absolute Maximum and Minimum Ratings

Table 2-6 specifies absolute maximum and minimum ratings, which lie outside the
functional limits of the processor. Only within specified operation limits can functionality
and long-term reliability be expected.

At conditions outside functional operation condition limits, but within absolute
maximum and minimum ratings, neither functionality nor long-term reliability can be
expected. If a device is returned to conditions within functional operation limits after
having been subjected to conditions outside these limits, but within the absolute
maximum and minimum ratings, the device may be functional, but with its lifetime
degraded depending on exposure to conditions exceeding the functional operation
condition limits.

At conditions exceeding absolute maximum and minimum ratings, neither functionality
nor long-term reliability can be expected. Moreover, if a device is subjected to these
conditions for any length of time then, when returned to conditions within the
functional operating condition limits, it will either not function or its reliability will be
severely degraded.
************************************************************************************
essentially operating between these two ranges the following could happen

(a) your CPU may not/does not work correctly.
(b) your CPU may not last as long as it would do otherwise.
(c) "the device may be functional" or it may not even if you go back below the functional limit, so the possibility of damage exists.
(d) if you exceed the Absolute limit you will probably (most likely) end up stuffing up your CPU.

And there you have it so no black magic involved or reading tea leaves etc,etc, if you want to know what your CPU specs are just look up the appropriate data sheet and read it, if you always stay below the FUNCTIONAL LIMIT VOLTAGE you will always be fine.

Hope this helps

Cheers

You quoted 45 nm CPU chart.
22 nm CPUs have MUCH smaller max voltages.

Yes that's correct as I just gave it as an example, if your interested in 22 nm CPU's , Xeons, Celerons or whatever then all you have to do is locate the appropriate datasheet for the particular CPU your interested in and read the relevant information concerned.

Cheers