[Bug 34237] External LCD monitor flickers every 30 seconds radeon mobility x1400

https://bugs.freedesktop.org/show_bug.cgi?id=34237

--- Comment #15 from Alex Deucher agd5f@yahoo.com 2011-03-02 07:28:27 PST --- (In reply to comment #14)

I've tried 2.6.38-rc6-git 7 (which seems to include Dave's drm-fixes) w/o any success. I still got intermitent black screen. For the record, my LCD is behind a KVM that corrupts EDID thus making the kernel to keep loudly complaining in dmesg

It it happens it regular intervals it sounds like some sort of polling. Have you tried drm_kms_helper.poll=0? Also, make sure knotify or upowerd are not polling the monitors regularly.