https://bugs.freedesktop.org/show_bug.cgi?id=87682
--- Comment #16 from Thom madeforspam@telfort.nl --- fb lower than 140 is possible, my current stock kernel 3.13.0-86 works flawless [drm:radeon_compute_pll_avivo], 6928, pll dividers - fb: 125.8 ref: 2, post 13
(sigh) I just wish I understood why some modes work and some don't