I have a supermicro box, 24 bays, little over 100TB in RaidZ6. The past few months it has started randomly rebooting, and sometimes it will give me a non-correctable dram ecc error detected and then give me a slot, sometimes it reboots back just fine. I've run memtest, I've pulled out all the ram sticks in all the slots it kept giving me (the slots kept changing). I thought it might have been an HBA card went bad (I have 3 of them) since this started a little bit after I added the 3rd HBA and last batch of drives so I replaced the HBA card. Thought it might be a boot drive so I replaced my boot drive. It has 2 PSUs in it and I did have to replace one of those a couple months ago. I've noticed that it does tend to reboot more often when I'm transfering data off the NAS and to another external drive. For the life of me though I can't figure out what the actual problem might be. The fact that it sometimes tells me there was a non-correctable dram ecc error detected made me initially think that maybe a stick of RAM went bad, but I have 18 sticks separated out into 2 groups of 9 on CPU1 and CPU2. When I get the error for say CPU1 Dimm1A, I take out all the sticks from CPU1 and then next time it would say CPU2 Dimm1A for example. I can't imagine all of the RAM sticks going bad or all the slots going bad, and it is weird that it tends to have issues way more often when I'm trying to transfer data, I'm kinda getting to my wits end. I did buy the unit used about 3-4 years ago if that helps any. I know I read that sometimes a bad PSU can cause weird issues, is there a chance I need to replace my other PSU? (The issues happened before the one PSU did go bad, so I don't think it is my new PSU causing all these issues). Any advice or input would be greatly appreciated, thanks!