I don't think you tried a different PSU yet. Doesn't sound like one, but it couldn't hurt since it's the only thing left. BTW PSU's need to have the dust blown out of them occasionally too, but if it's acting up already it's too late.
On your next install attempt...
Go into bios and set "safe settings" option on the main screen. The name varies with the version. Then go in and turn off all the extras - Sound, Lan, USB 2.0, etc. That will let you see if just the bare essentials are working. If it still doesn't load you're screwed.
On your next install attempt...
Go into bios and set "safe settings" option on the main screen. The name varies with the version. Then go in and turn off all the extras - Sound, Lan, USB 2.0, etc. That will let you see if just the bare essentials are working. If it still doesn't load you're screwed.