I have never used an SSD as a replacement for internal storage on an xbox, but you plug the drive into the console and you need the OSU1 update http://www.xbox.com/xboxone/osu1 on a USB (format USB to NTSF). When you turn the console on it will boot to safe mode and show a system error ranging from E101-106, go to troubleshoot and then offline update and it should work. Also you do not need to pre-format HDDs anymore for xbox, you can plug it straight in and the console formats the partitions itself. If it doesn’t work then I suggest trying a (min storage 500GB, max 2TB) 2.5” HDD, seagate barracuda greens are a good HDD to use.

http://trenpenn.com/repair/ you can look for local shops to send it to to be fixed, most shops also allow mail ins

My experience with Xbox S’s and display issues are it’s either the Hard Drive needs replacing, or it’s the HDMI transmitter chip if your HDMI port is visually fine. When you replaced the hard drive did you do the formatting it needed?

Recheck your psu is plugged in properly, the fan is plugged in properly etc. Also check your thermal paste.

Could be a dying battery or power issue on the motherboard by the sounds of it

if both triggers are acting up then it could be the daughter board. There’s no damage to the chassis holding the triggers in?

did you use something like this? http://www.chemtools.com.au/product/elec...-electronics/production-rework/heat-sink-compound/ also is the fan plugged back in to the motherboard?

if your HDMI port isn’t damaged then it most likely is the HDMI Transmitter chip on the motherboard. It’s the most common problem with display issues, that or it’s your HDD failing.

It sounds like it could be that the motherboard is the issue

If it’s your controller movement then it’s a drifting analogue, fixing it would be pointless IMHO