I wonder whether your observation about refresh rate isn't on the right track. The drop-down list in Settings > Displays > Samsung Electric Company 22" > Refresh Rate is as follows (in Hz):
120.00 110.00 100.00 89.94 59.95 59.88 The default setting is for 59.88Hz, where I get clipping. If I change to 59.95Hz then I cannot seem to trigger clipping. When swapping from 59.95Hz to 59.88Hz, though, I get immediate clipping. Clipping is also induced when I select 100.00, 110.00, or 120.00; at 89.94Hz, the entire screen is black. The only reliable performance appears to be at 59.95Hz. Therefore, your earlier suggestion to try different refresh rates is the likely solution, here. However, I would expect to see stable performance at least at 120Hz, that being approximately an integer multiple of 59.95Hz. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2074559 Title: [nouveau][Samsung SyncMaster] Top margin of secondary monitor covered with black flickering rectangle To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2074559/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
