[Bug 48772] Signal unstable over Display Port on 2560x1440 monitor

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=48772

--- Comment #3 from Alex Deucher <agd5f at yahoo.com> 2012-04-16 08:43:47 PDT ---
(In reply to comment #2)
> radeon.disp_priority=2 seems to have no effect. Perhaps it decreased the
> frequency between screen blackouts, but my sample size is small and randomness
> of the timings makes me uneasy to claim so yet. Would it make sense for it to
> have such effect?
> 

Sure.  Setting that option sets the display priority in the memory controller
to the highest possible level. If the MC is still having problems keeping up,
it may be that your system can't handle a monitor that big.

Alternatively, your monitor may not like the set of pll dividers selected by
the driver in this case or spread spectrum settings.  You might try setting the
RADEON_PLL_PREFER_MINM_OVER_MAXP or RADEON_PLL_USE_FRAC_FB_DIV pll flags in
atombios_adjust_pll().

What link speed and number of lanes are being used for that mode?  Does the
monitor support downspread?

Does the proprietary driver work ok with that monitor?

> Is testing with tiling disabled relevant given the problem happens also without
> X running?

That should be equivalent.

-- 
Configure bugmail: https://bugs.freedesktop.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.