Okay, so I removed the x-clamp and put screws instead (as well as new thermal paste). I let the xbox overheat, then turned it on after it cooled a little while and it worked. I haven't been able to test it for any length, because I don't have means to charge my controller for the moment. Anyway, my concern as of right now is with the screw setup, there isn't really anyway to tell whether or not I'm crushing the cpu or gpu. I tightened the screws, but stopped right when it got to the point of having to use any force to tighten more. Is there any way to tell whether or not I'm doing damage to it? I have four washers (two nylon, two metal) on each screw. Also, for anyone who's done this, was it hard to get the mainboard to fit back in the case. I'm a little worried that the screws are too big, even though in reality they shouldn't be any different from the x-clamp.