On 05/08/11 1:11 PM, John R Pierce wrote: > On 05/08/11 1:03 PM, Jason Pyeron wrote: >> If you can use less drives, this would be more cost effective (time building& >> time fixing) >> >> http://www.newegg.com/Product/Product.aspx?Item=N82E16811219038 [400$] > > multiple reports online indicate that norco case is very flimsy and > poorly made. ooops, hit send too fast. also, that Norco case appears to require a seperate SATA channel for each of the 24 drives while the supermicro case has SAS2 multiplexed backplanes that will let you put 24 SATA drives on a single 4 channel SAS port, or 24 dual ported SAS drives on 2 4 channel SAS ports (using MPIO)... these backplanes have SES controllers on them for power and hotswap management (the SES functionality is integrated into the LSI SAS multiplexor chip used). note that SAS supports N:M multiplexing where any one of the N controller channels can address any of the M devices.... plain SATA only supports 1:M simple expanders And, a significant problem in large drive arrays is mechanical resonance.... you get an array of 24 or whatever disks all being hammered at once in a RAID environment, and the mechanical vibrations can cause interactions which can increase the error rate, this is greatly compounded by a flimsy chassis.