OK, this is perplexing me. A week ago we installed a 512mb cache DIMM with battery, and a week later (SURELY enough time for the battery to charge) and we're getting sustained write performance of about 15MB/s, up from 2-4, but nowhere near what it should be. The array is 3 x 450GB 15K SAS disks. I haven't looked closely at the burst speed, but surely when doing sustained read/write operations (eg. backups and restores) you would expect faster performance than 15MB/s!!! A saturated USB2 bus can usually manage 30-35MB/s consistantly. Any thoughts?

Thanks very much for sharing the info, since this server is located at a remote site, I'll wait until out next on site visit and let you know the results once I've updated the firmware.