Sparc32 systems and power consumption
I have both a collection of sparc32 systems (2x SS20s, 2x SS5/170s, 1x SS4) and
a very strong interest in low power in systems that run 24/7.
As a result I've done some power measurements on them in order to find the lowest
power system that will do what I need.
(All of the below should have "In my experience/with my measurements/etc" stuck
I don't see any important power consumption difference whether the systems
are idle or not. I actually see a decrease when I use a new fast scsi disk
vs the old 1 and 2 gig disks these came with from Sun. In all cases they
are maxed out in memory as well so that draws some extra. Finally, this is at
220V so the power supplies might be more or less efficient at 110V. In some
cases I've used the SS4 50 watt power supplies and in other cases I've used
the SS20 150watt power supplies and I don't see much difference in consumption
between these two power supplies in terms of efficiency. My guess is that
these power supplies aren't so efficient in converting power.
>From lowest to highest, measurements taken at the power plug.
SS20/Dual 100 hypersparc 75watts
SS20/180 Hypersparc 77watts
SS20/Dual 55 hypersparc 80watts
SS20/60 Supersparc 80watts
SS20/85 SuperSparcII 80watts
SS20/133 hypersparc 85watts
SS20/200 hypersparc 90watts
SS20/Dual 90 hypersparc 90watts
SS20/Dual 142 hypersparc 115watts
For the benchmark I was running when doing this test, to round numbers,
the speed scaled with the clock speed.
In general these systems were running NetBSD, but, Debian Sarge
was used on the SS4 and the SS20s with SuperSparcs as well with
no major changes in power usage.
Just a few other numbers with newer systems:
300mhz Ultra10 90watts
Mac 7300/200 100watts (two disks though)
Dual 400mhz Ultra2 180watts (two disks though)
I am a big SPARC/PPC fan and not a big x86 fan, therefore I was quite
disapointed to find a cheap Dell 500mhz PIII drawing only 55 watts or so.
So, 2x faster than the Ultra 10 and 1/2 the power (round numbers).
As someone else pointed out though, a NSLU2 is very very low power
(my watt meter doesn't measure it). It's even lower power than some
cheap 8 port Netgear switch (at 11 watts). The house server is a
NSLU2 because of that.