R: Radeon HD 5770

hi johannes, for have the radeon work is need to play with yaboot kernel append options, here my shared experience with ubuntu communty. [PPC] Instruction for Install Ubuntu & sons on PowerMac G5 Quad with Radeon HD [Archive] - Ubuntu Forums

R: Radeon HD 5770

HI, i had been test linux with G5 Quad . Quadro 7800Gtx in 16x slot, radeonhd on 8x slot. Result, it work with mesa 3D enabled on 4650, 5450, 6570, and R5 220. only 2D working with SI cards 7750, r7 250 because mesa crash for endianess someware. For have the PC bios card working you need 2 Monit