Heat / Wattage Output - Barton Desktop vs. Mobile

[DamnDirtyApe]

I realize that most people who have these Barton mobile CPU's are using them for overclocking at high voltage, but I'm curious about using one of these instead of the desktop version because of the lower voltage. I have a Shuttle XPC, which can get pretty toasty with my 2500+ at full load. Does anybody have any quantitative data on the wattage used by the following combinations? I'm no physics expert, and have no idea if Mhz alone affects heat output...

- desktop 2500+ @ 1.83 Ghz, 1.65V
- desktop 2500+ @ 2.2 Ghz, 1.65V
- mobile 2500+ at 1.83 Ghz, 1.45V
- mobile 2500+ @ 2.2Ghz, 1.65V

I have a faint recollection that there's some formula to calculate wattage based on volts & amps, but the formula itself is eluding me...

 

[Mingon]

A 2500+ mobile or Xp will likely produce the same heat at the same voltage/speed.

 

[beatle]

MHz does affect heat, though not as much as voltage.

Remember P = VI (wattage = voltage x amps) so a cpu that's consuming 53.7 watts @ 1.65V is drawing 34.73 amps. Change that to a mobile cpu @ 1.45v and you'll get 1.45 x 34.73 = 50.4 watts. That's not very significant, but it may not be accurate. There's still no entry for mobile cpus on sandpile.org.

BTW, a 2500+ @ 2.2GHz is a 3200+ which uses 60.4W of power, so MHz does mean something.

 

[Jeff7181]

Section 6 & 7

 

[Noid]

.op

(I was going to post tech doc on the XP-M , but that AMD section is 'down')

 

[Insane3D]

Also check out the XP-M 2600+...it theoretically will be the "best of the batch" since it runs @ almost 3200+ speed (2.13Ghz), but @ only 1.45v. The one I just picked up does 2.2Ghz @ 1.45v (default), 2.3Ghz @ 1.5v, 2.4Ghz @ 1.55v, and 2.5Ghz @ 1.65v, where it currently resides. As usual, YMMV. Even at the minimum, these could basically be considered 3200+ @ 1.45 - 1.5v...a good deal below the 1.65v of the desktop 3200+.

 

[DamnDirtyApe]

Man, these things sure look good. However, I suspect if I picked one up to run at low voltage it would still eventually end up being overclocked to the max!