What I've seen most is issues with drivers. Even AMD, whose open GPU drivers make/made the planned included supplier of GPUs for this notebook have said that yo

What I've seen most is issues with drivers. Even AMD, whose open GPU drivers make/made the planned included supplier of GPUs for this notebook have said that you're on your own on big endian systems. If you use the PCI Express slots on your 2005 Power Mac G5 to add a modern-ish (<12 years) AMD GPU to your big endian ppc64 system, it will give you a picture alright but 3D effects sometimes get corrupted and the hardware video decoder flat out does not work. The AMD driver simply implicitly assumes their platform is little endian in many places. And that's not really a surprise. The only big endian system available to mere mortals that can fit an AMD GPU is a noisy, heavy, oversized metal box from 2005 you need to get off of Craigslist. Even the Raptor desktops default option is ppc64le. Most hardware developers never need to worry or care about big endian hardware, as none of their users use POWER, SPARC, S390X or something even more obscure. This driver case is where AMD has made an explicit statement (though you'll have to forgive me from backing that up, can't find it anymore). In other cases it can be hard to differentiate between regular software bugs and endianness specific bugs.