Felger Carbon wrote:
> Does anybody know how much power the 90nm K8 dissipates?
That is a moderately broad question. How fast and how much L2?
By my own measurements, a 2 GHz Opteron 246, E4 stepping,
dissipates about 65 W and a 2.6 GHz Opty 252, E4, is about 77 W.
(My measurements method was to take the difference between the
power drawn by a 2P system with both CPUs running and the same
system with one CPU disabled. I assumed PSU efficiency of 65%.)
At the same speeds, the Athlon FX and the 1 MB L2 versions of
Athlon64 chips at the same as the Opteron thermally. 512 KB L2
versions of the Athlon 64 should use a little less.
There are also low voltage (and very expensive) "HE" versions
advertised as 55 W max for the Opty x46, and x48.
The reason I
> want to know is, there's a .37C/W HSF (heatsink/fan) available whose
> noise level really is 21dBA.
FWIW, I have tried the AlCu versions of the Zalman CNPS7000A and
the CNPS7700 in Opty dualies using the 246, 250 and 252, and in
single Opteron systems using the 148 and 150.
They do the job and run *very* quietly.
Beware of the large size and weight of the 7700. If you have any
doubt about your ability to squeeze one into your system, get the
smaller 7000 instead.
http://www.zalmanusa.com/usa/product...x=142&code=005
http://www.zalmanusa.com/usa/product...x=146&code=005
I have never tried the pure Cu versions of those fan/sinks:
their huge weights intimidate the hell out of me.
>
> A Thermaltake subsidiary(?), TR2TT, has a 21dBA 32.4CFM 2500rpm 80mm
> fan that they use in 4 HSF models:
>
> AMD K7 TR2-M3 (TT A4004D) .48C/W
> P4-478 TR2-M5 (TT A4005) .48C/W
> Prescott TR2-M12 (TT A4012) .42C/W copper
> AMD K8 TR2-M6 (TT A4006D) .37C/W copper
> [TT = Thermaltake]
>
> The P4 model is hard to find. But Froogling the TR2TT part # or the
> TT part # will reveal single-digit pricing (US$) on the others. And I
> know of other single-digit prices that don't show up on Froogle.
>
> A long time ago in a galaxy far away, I spent 8 years running a
> company whose business was building environmental acoustic noise
> monitors - sound level meters with a built-in microprocessor for
> unattended statistical data gathering. I have some real-world
> experience in measuring low noise levels.
>
> So I didn't believe it when I saw HSFs speced at 21dBA. I bought one,
> the M3, to disprove it. I was wrong. Late at night I turned off
> everything in my house (not apt) and used a 12V lead-acid battery for
> power. At 6 inches, I could barely detect the fan noise. Then the
> refrigerator came on, 20' away around a wall, and I could no longer
> hear the HSF even at 6" (quiet refrigerator).
>
> I'm guessing that automated fan/rotor balancing is used to achieve
> this low noise level. Other makers have 21, 20 and even 19 dBA
> fan-based HSFs, so the technology (which is really fan technology) is
> becoming widely available.
>
> These fans don't move a whole lot of air, so they can't be used -
> yet - to cool a 92W .13u Athlon64. But I think the 90nm version, now
> available across the counter, can get by with a .37C/W HSF. Can
> anybody confirm that with actual power levels?
>
>