https://bugs.freedesktop.org/show_bug.cgi?id=48880
--- Comment #17 from Tvrtko Ursulin tvrtko.ursulin@onelan.co.uk 2012-04-19 06:59:00 PDT --- (In reply to comment #16)
(In reply to comment #14)
I'd be leery of changing the pll flags without a lot of thorough testing since these change may break certain modes on other monitors. Did you try RADEON_PLL_USE_FRAC_FB_DIV? It should help the driver get closer to the actual pixel clock by allowing a finer grained fb divider, but once again, some monitors are picky about certain divider combinations. I'd be more inclined to add this flag than the MINM_OVER_MAXP flag however.
I haven't tried RADEON_PLL_USE_FRAC_FB_DIV yet, but will now. What are the downsides of that one? I suppose there must be some since it is not enabled by default...
This flag also fixes it.