Maybe it overheats the CPU and fries the chip? I think that is the only way that the whole unit would broke beyond (cheap) repair, if it just corrupts internal flash then the manufacturer should still be able to fix it.

I think I will first downgrade to V25 and then back to V26. Just in case since there are reports that the official V26 still has the 3D function build-in and enabled if you do just V26 downgrade.

Who knows, maybe this is just scare tactics from the tester. But I sure wouldn't like to buy another navi computer because of this.