I just added a new rx 580 8GB XFX to my rig and noticed that it was not like the others bought in the same batch (directly from store). This one says in GPU-Z that it is Samsung memory (like the others), but when i was about to BIOS mod it, it first asked me which version of ubermix i would like to use and then I saw that is was both Samsung and Micron.
How is this possible? I didnt knew it could be a mix.
When i used it with the modded BIOS the mh/s just went crazy and said it was doing 40-60 mh/s lol! (i know it is fantasy numbers and will only result in bad shares). But with the same settings the GPU Only drew around 75-80 watt and my others (same GPU’s) are around 115 watt/GPU.
I got so many questions… 
I had to revert back to stock BIOS because it would crash after a few minutes even with small changes to the mem and core. So im back to 26 mh/s on that card 
Anyone else had a card like this, i mean with mixed memory and can give me some hints how to BIOS mod and get those extra mh/s
Have a great day!