Am Montag, 02.02.2015 um 18:57 schrieb Sid S <r03...@gmail.com>: > I don't think anybody is capable of giving you a firm answer because > nobody has done it. You would probably be the first. In fact, when > double-checking the info I had found earlier, some of the searches > gave your message in the first 3-4 results. Hi Mom! > > Cards which support UHD should support 4k. You can try to use the > closed driver benchmarks from Phoronix to guesstimate if your intended > usage will be passable > (http://www.phoronix.com/scan.php?page=article&item=ubuntu_1404_4kgpus). > The R7 250E may have issues running a composited desktop. I would not > expect the R9 280X to have issues. Most complaints seem to be from > people with older cards, but then again, those reporting success all > seem to be using closed drivers. > > I rated success likely enough that I was considering a Dell P2415Q w/ > the Intel HD4600 (and replacing my motherboard) or an R9 290X. Make > sure you have an exit strategy, though.
Today I exchanged my Radeon HD4550 video card in my gentoo workstation with a R7 250E. It seems that it works with xfce and composite desktop without problems. The only problem that I now have is the tearing, that occurs when I watch HD videos. The EXAVSync parameter doesn't work with glamor acceleration. When I switch to EXA acceleration I have no xvideo extension and cannot watch videos at all. Maybe I will find a solution for that, but I'm not sure. At the moment I use my old monitor with 1920x1200@60Hz. In a few hours I will get the new monitor. Then I will try to use it with 4096x2160@50Hz. Because all my videos are using PAL standard I have a very little hope that with 50Hz the tearing will disappear. But I fear that the tearing will even gets worse because of the higher resolution. The R9 is for my other machine, which I use for graphics work (RAW conversion etc.) This is a dual boot (gentoo and windows 7) but it mostly run under windows. When the R9 runs much better under gentoo than the R7, I maybe will buy also a R9 for my gentoo workstation. But then I must replace my passive cooled power supply unit too. And I really don't like noisy computers. That's the main reason for the R7. It's cooled passive and it works without problems with my silent 450W power supply unit. The other reason is that I have to spent about 400€ for the R9 and a new power supply unit. P.S.: Much thanks for the hint about the composite desktop. I deactivated compositing and the tearing is gone. :-) As it costs only a click in the xfce settings I can switch it temporarily off without problems when I wanna watch videos. Regards wabe