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Please see link to 10 images of board here https://imgur.com/a/nJotOX1 The machine in question is a v1.0 with fresh electrolytic capacitors installed everywhere a few weeks ago aside from the power supply (Foxlink, with resoldered power leads). It also has an Aladdin mod chip which I was running Cerbios 2.2.0 beta on previously. After successfully upgrading the RAM on a v1.4 machine yesterday I decided to do my primary xbox today. RAM in question is the leaded F-QC50 variant. They appear entirely to be authentic Samsung chips. With XBlast OS flashed to the mod chip, I began with the RAM install. First chip, test, success. Second chip, test, fail. Quick rework and second passes. Then I decide to do the last two together and test afterwards. Test shows 1-3 pass, number 4 fails. This is the one below the CPU and next to the connector from the power supply. Rework number 4 with an iron, not hot air, still fails, rework it again, still fails. Go for a third try and now the Xbox will momentarily boot with solid green LEDs (hard disk spins up, fans spin normal speed, LED on mod chip illuminates) then quickly cuts power. Then will turn itself on again about a second later, usually with no LEDs on the eject button, fans spin normally, LED on mod chip lights, then power cuts out. There is no display. I also swapped in a known good power supply from a different v1.0 and no difference was made. This cycle appears to repeat indefinitely. Sometimes the LEDs on the eject button light up green, sometimes they flash green, other times there is no light at all. I have tried with no disc drive and no hard disk, with just one of those, and with both of them. I removed the fourth RAM chip in an attempt to rule out the chip itself, however the same result ensues. I then removed a factory RAM chip (M-QC50) from a known good console and installed that in the fourth slot, no change. I ended up removing that chip so only ones that passed the test in XBlast are installed. I know it is possible for the chip to be bad, yet still pass. I took the utmost care not to “splash solder” around while installing and/or removing the memory. I taped up the surrounding areas of the board and components with kapton tape before performing any work with hot air or an iron. High quality flux was used and cleaned up. I examined the board thoroughly multiple times and I cannot physically see an issue. Using hot air I carefully reflowed the factory RAM as well as the three that I added. My question mainly is where should I be looking for a solution to this issue? This is not the typical 3 reboots then FRAG problem. Is there a power related component I should be looking at? Any help is greatly appreciated.