Whoooooohooooooooooo!
Ok. So, I updated to dash 16537, and for some reason it worked (no awkward results), but I could not play any games as it kept freezing. It also froze randomly in FSD and Retail Dash. So, and after LOTS and LOTS and LOTS of modification and testing with Power Modes, Power VCS Control and ANA Fuse Values, I found one working perfectly!
Power Mode: 8080
Power VCS Control: 8565
ANA Fuse Values: Both 3
What I noticed: My original Power Mode was 8280, on 8180 it glitched perfectly with 90% instaboot, but the games kept freezing. On PM 8080 and PC 8555 the glitching was bad and kept RROD with 3 lights (0010 I think). Changing the ANA Fuse Values did not render better results in all cases.
Its still a shame that I can only run 1 USB device (500gb external), more than that freezes the console or some weird GPU glitching takes place (Micro dots on the screen, and lots of flickering) but ey, beggars cant be choosers right
Now enjoying Ultimate Tenkaichi for the last hour without any problems.
Many thanks Mr MartinC, who knows, maybe someday I can help YOU out with something
Adios!