On Thu, Aug 21, 2008 at 15:13, mike <[EMAIL PROTECTED]> wrote: > I'd be using either a Lian-li case or a Cooler Master CM Stacker case. > Depends on if I decide to do 10 drives or 15 drives. I have to figure out > power supply requirements, I am not sure I can do 15 drives off a single PSU > properly, or at least I need to make sure the components support staggered > spinup and won't load the OS until the devices are all ready (otherwise ZFS > would throw a fit!) A good rule of thumb for non-staggered spinup is 3A on the 12V line for each drive that needs to spin up. So for 15 drives you need 45 amps, plus whatever the rest of the system takes. On the other hand, steady-state draw is only about 1A, and one should plan to have two drives spinning up at once, so with staggered spinup you need at least 13+2*3 = 19A. It's also wise to tack on 20% or so extra capacity to your power supply to account for capacitor wear over time and the fact that PSUs are generally less efficient at full load.
> My goal here is the quietest machine possible so I need to shop for quiet > PSUs that will support 15 drives if I go that route. Any ideas/product > suggestions are definately appreciated. I have a Corsair TX750 that is quiet, reviews well [1] and is only about $120 now. It claims to produce 60 amps on the 12V rail, which is enough to do 15 drives. I'm only running four drives on it now, but I once ran 15 drives on a good quality 550W power supply [2]... not that that's recommended. When reading power supply reviews, it's important to look for real load tests done with a tester, not just "we plugged it into this machine and it worked". Most real machines don't draw very much even at full load---my Q6600/4G/4x750 file server only draws 140 watts from the wall---so these tests don't push a power supply as hard as you're likely to. Some good sites for this are [3] and [4]. Will [1]: http://enthusiast.hardocp.com/article.html?art=MTQwMywxLCxoZW50aHVzaWFzdA== [2]: http://www.newegg.com/Product/Product.aspx?Item=N82E16817103437 [3]: http://jonnyguru.com/modules.php?name=NDReviews&op=Review_Cat&recatnum=13 [4]: http://enthusiast.hardocp.com/reviews.html?cat=NDUsUFNVIC8gUG93ZXIgU3VwcGxpZXMsaGVudGh1c2lhc3Q= _______________________________________________ storage-discuss mailing list [email protected] http://mail.opensolaris.org/mailman/listinfo/storage-discuss
