Hay Guis!
I've repaired about 25 Xbox 360's that was suffering from RROD in different forms with X-clamp-kit, and it's seemed to work pretty good so far.. Haven't gotten any complaints..
But..
I recently started to repair a couple of pretty hardcore RROD malfunctioning XBox 360's that had been "fixed" with x-clamp-kit before, as well as done the "heating-trick" underneath the GPU.. But now they suffer artifact screens like this:

as well as highspeed-fan at beginning..
Now, anyone got any advice on how to fix this? Ive tried the 20-min heatup while RROD with not fan connected and then cooldown for 20 minutes, as well as heating up the underside of the motherboard at the GPU area, (which in other cases did the trick), but it seems that Ive got no more options left..
Halp?!