I upgraded the hard drive in my Roamio TCD846500, thinking it had failed. When that didn't solve the problem, I thought it might actually be a bad wall wart. Now I'm not sure what's going on. Please excuse the long post, but I want to thoroughly explain my process in anticipation of the questions that might arise. Over the past year or so, I experienced periodic pixelation and unexpected reboots with my 3TB WD30EURX. I ran Kickstart 54 & 57, but it seemed yield little improvement. When it rebooted and got stuck in a reboot loop a couple of weeks ago, I thought the drive had finally encountered an unrecoverable error. I reinstalled the original 500GB Tivo HD and everything started up normally, which made me think again it that the 3TB HD was causing the problem. I purchased a WD Red WD40EFRX 4TB, ran the full WD diagnostic test with no errors found, installed in the Roamio to grab the OS, then ran MFSR to gain full access to the 4TB capacity. I went through the entire guided setup and checked account info to confirm I had 638 hours HD capacity. As expected, I had cable card pairing and tuning adapter issues, so after some time on the phone with a Charter/Spectrum tech, she scheduled a tech to come out the next day. Prior to the arrival time, I moved the Roamio from my workbench to my TV location. When I plugged it in, the whole reboot loop started again. I tried everything in the short time available, but could never get out of the loop. I found two other issues in various threads that referred to the reboot loop: (1) a software update a couple of years ago that caused a loop when connected to Ethernet, solved by another software update a short time later; (2) stock Tivo Roamio wall wart going bad (seems to be a lot of controversy about this), and/or not being able to supply enough current for larger drives. Today, I tried a new 12V 2A wall wart from another device, but still had the loop. I then unplugged the USB cable for the tuning adapter and the Ethernet cable and the Roamio booted to the "no tuning adapter" screen. I cleared that and had access to live TV, minus premium channels. Connected USB & Ethernet and no go. I re-checked all SATA and ribbon cable connections on the motherboard. Next I pulled a 12V 4.16A brick from another device, plugged in with USB & Ethernet and went into the loop. I disconnected the Ethernet & USB, reconnected power and Roamio booted right into My Shows with live TV in the upper right. I connected Ethernet & checked Network menu, which showed connection in progress Loading Info. When that finished, the Guide info was up to date. Many, but not all, premium channels are now available. I've not yet connected the tuning adapter USB, but that's where I am now. I'm on software version 20.7.4.RC18-846-6-846. I've done a search, but have not found what the current version should be. Should I force a software update? If it downloads new software, will I lose my expansion to 4TB and have to run MFSR again? At this point I'm stumped. I thought the beefier power supply would be the fix, but apparently not. Any thoughts, comments or suggestions would be greatly appreciated.