Power consumption in desktop computers

[Don Lewis]

A few more data points:

System 1 (FreeBSD 4-STABLE)
  Pentium II 400
  Asus P2B-LS motherboard (fxp + aic7890 Ultra2 SCSI on board)
  384 MB ECC RAM
  Matrox G20
  Floppy
  Seagate ST336737LW
  Seagate ST39173LW
  Plextor PX-R412C CD-R
  Tandberg SLR-5
  Floppy
  Supermicro Case with lots of fans
  Idle:       72W / 112VA
  Active:     88W / 134VA


System 2 (FreeBSD 4-STABLE)
  Aopen AX34-U motherboard
  1 GHz Celeron underclocked to 668 MHz (66 MHz FSB instead of rated 100
    MHz)
  256 MB ECC RAM
  cheap PCI video card
  IBM IC25N010ATDA04 10 GB laptop drive
  1x sis ethernet
  1x fxp ethernet
  no floppy
  90 W (?) power supply
  Active(?): 39 W / 57 VA


System 3 (FreeBSD 5-CURRENT)
  Gigabyte GA7-DX+ motherboard
  Athlon XP 1900+
  1 GB ECC RAM
  Adaptec 19160B SCSI controller
  Seagate ST336706LW
  ancient NEC CD-ROM drive
  fxp ethernet
  g-force 2mx video
  floppy
  Antec True Power 330W supply
  Idle:     135 W / 198 VA
  Active:   153 W / 223 VA


The power measurements were made with a Radio Shack "Kill A Watt" meter.

System #3 is my second fastest machine.  My 1.5 GHz Pentium-M laptop is
slightly faster on the "make buildworld" benchmark.  I haven't gotten
around to measuring its power consumption yet, but it runs a whole lot
cooler than the Athlon and its power supply is rated at 72 W.

The newer Athlon processors would be interesting, except that I haven't
found a motherboard that supports them with ECC RAM.  About the only
Athlon motherboards that support ECC RAM use the AMD 761 chipset, which
is getting rather dated.

Has anyone done power consumption measurements on amd64 systems?

There are some Pentium-M motherboards available now that support ECC
RAM.  They are targeted at the embedded market and are fairly pricey,
but I would expect them to perform well and have low power consumption.