Is it possible some CPU's do produce more heat than others?

[agarza]

Let's say my Dothan 1.8GHz generates much more heat that is suppose to generate:

Undervolted, the CPU temp rises to 48-50C. The GPU to 50-54C underclocked also.

Could this be caused by some manufacturing incontrollable variables that result that a determined manufactured lot have this problem, and hence people reporting getting a very hot Thinkpad?

[FTC]

Hi,

I would say yes, anot all CPUs are equal. Once this is said, note that it is not only the manufacturing variables that affect, but also many other parameters such as :

- The program running, (or even the idle loop running, which could load the CPU differently even with different service packs or 'background' devices running),
- The power saver mode the CPU is being use (i.e dynamic/full performance,..)
- The voltage the CPU is being feeded...
- The Heatsink/fan being used, (i.e 'long' or 'short'),
- How it (the heatsink) is mounted,
- The thermal interface material in use,
- The fan settings (i.e at what temperature does it activate and at what speed... this depends on the BIOS version mostly).
- The surface the thinkpad is standing on,
- The external temperature,
- The other chips the CPU is 'sharing' temperature with (i.e GPU)
- The accumulated dust in the fans
- Other 'hot components' being used, i.e wireless card which can also heat up the machine...
- Filled/empty areas in the thinkpad (PCMCIAs, ultrabay,...) which can change airflow,...

All in all, each of those could mean a small additional variance... but together can fully explain all the different 'sample temps' we are seeing reported.

[Thinkpaddict]

There is some variability definitely, even within exact same models.

I even remember vaguely reading a discussion where someone pointed out that the only difference between Celeron processors and Pentium III Processors (when these two were the two mainstream processors from Intel, before the Pentium M and Pentium 4) is that Celerons are Pentium III processors that didn't make the cut in the QA stage. That is, if it heats up too much under the specified frequencies, just rebrand it as a Celeron, put less cache on the chip, etc.

[gauthier]

I experience different results with two identical speced t40p: at low freq (600mhz), first one work well undervolted (0,7v), while other freeze after few minutes with same settings.

Temp is a bit higher (39-43°) with the undervolted while iddling, the other one keep < 38°.

If I was inclined to do so, there would be much to be said, but it's clear (IMHO) that each cpu has it own "spec"

[agarza]

Indeed. However my CPU is the hotest of all you people. 50C undervolted. Can't keep in the low 40's (UNDERVOLTED, of course(

[Bgradid]

There are always variations in cpu's of course, but, I would expect temperature differences to be much more likely a result of the heatsink and room temperature of course (all other variables aside, asuming idle use)