Hi, my thermal mod is working fine too. I used a 15 x 15 x 1 mm copper pad above the Atom CPU because a 20×20 would reach too close to other electronic components. I cut another 15×15 pad in half and put each part strading two RAM chips. I cut a 1 mm thermal silcone pad to the proper shape, holding the copper pads in place and covering the flash chip too.
I applied artic silver thermal paste on the chips (and you can see stains of it on the silicone), and after closing the EMI shield y put 4 15x15x1 mm copper pads between it and the back plate. I re-used the silcone pads that came with the tablet and put them around the copper pads.
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