On Wed, Oct 15, 2008 at 23:51, Scott Laird <[EMAIL PROTECTED]> wrote: >>> Most 3.5" drives want >>> about 30W at startup; that'd be around 780W with 16 drives. >> I'm not sure what kind of math you're using here. > > See > http://www.seagate.com/staticfiles/support/disc/manuals/desktop/Barracuda%207200.11/100452348b.pdf > > Seagate claims 2.8A @ 12V per drive at startup. That's 33.6W. The > operating draw is way lower--the last time I measured my E2160 + 10 > disk system drew around 130W while idling and not a whole lot more > while active. 2.8A at startup sounds about right. I still like my 20W-per-drive rule of thumb for home systems; well-built power supplies can momentarily deliver more than design power to account for spinup, and in the event of a failure one can RMA or replace the dead supply with little impact. But my original point was that 16 times 30 is 480, not 780; 300 extra watts for a system is something I'd expect to see from a 16-core machine or something. There's some advantage to allowing overhead in one's power supply choice (capacitors aging), but 40% is a bit much.
For work use, of course, design for redundancy and uptime. But for most things I'd use a home server for, spending that kind of money is a waste. Money one would spend on a gargantuan power supply to sit in your basement is generally better invested in an off-site backup, even if all the difference buys is a DVD that you leave at Grandma's house when you visit. Will PS: None of this stops me from wanting the work-grade stuff at home... _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
