Ok, much playing later and I *may* have found the source of the problem with the RAID 5 build. If I build a 4 disk RAID 5 unit on the second Plextor Ultra100 TX2 controller then it works perfectly and the system keeps running. The second I introduce a single disk from the first controller it all goes horribly wrong. To me, this appears to indicate a fault in the first controller. I'm going to order a replacement and see if that solves it. I'll let the list know either way. Thanks for all your patience! Please don't CC me on anything sent to mailing lists or send me email directly unless it's a privacy issue, thanks. -- Rob | Ask questions the smart way: http://www.tuxedo.org/~esr/faqs/smart-questions.html _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp. - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html