I've posted about this problem on two other forums (and emailed Promise directly) and have yet to receive a single response, but someone suggested I try here, so here goes... I've just set up a small RAID5 array on a Promise SX4000. My first indication of a problem was just after installing the card. The SX4000 BIOS took a long time to scan my drives, in the range of 10-12 seconds. It only takes about four seconds in another PC. The next clue came during Promise's array management software's initialization of the array, which took somewhere around 15 hours. I'm by no means an expert on the subject, but that doesn't seem quite right. Lastly, benchmarking the array gives me results slightly slower than that of a single drive (which I tested before putting the array together). To be honest, I don't really care about the speed of my reads or writes - I chose RAID5 for redundancy, not speed - but it's kind of disturbing to see the numbers. The only problem I've been able to find is an I/O Range conflict with the DMA controller. The SX4000 uses 0000-0002, the DMA controller 0000-000F. Is it likely that this conflict is the cause of the SX4000's sluggish performance and if so, is there any way to assign a different I/O range to the SX4000 (since I'm not permitted to do it through Device Manager)? Any suggestions, tips, comments, etc., would be very welcome and grealy appreciated.