Radeon HD 6450 with fedora 17

[cottrellnc]

Just updated to fedora 17 (x86 64-bit) via an install DVD plus the latest online updates. I'm suffering from stange video problems that weren't there in fedora 16. The box is a Dell XPS 8300 with Radeon HD 6450 (CAICOS) graphics, driving an HP L1906 flat-screen monitor at 1280 by 1024. Gnome tells me the driver in use is Gallium 0.4. Xorg.0.log shows ati_drv, radeon_drv, vesa_drv and fbdev_drv modules loaded.

So what's happening? On cold boot I'm getting one or other of the following effects:

1) Worst: a black screen with a tiny flickering margin at the top. No way to do anything with the system, power-down required.

2) Bad: full-screen video but pale and severely flickering. Possible to interact with the system (log on) at risk to eyesight!

Here's the strange part: if I manage to log on, I can then suspend and resume, and the video comes out clear as a bell (as it was all the time with fedora 16).

[cottrellnc]

Things seem to be have stabilized on effect 2) above: pale and flickering video on boot. The initial grub screen is fine, but graphics bad. Suspend/resume seems to work reliably to get the graphics to come right. Any thoughts?

[tashirosgt]

Originally Posted by cottrellnc

So what's happening?

Start by determining how your video hardware is detected. http://forums.fedoraforum.org/showthread.php?t=280420

I tried that on FC 17 this morning and noticed the output no longer distinguishes between "module" and "driver". It just says "Kernel driver in use".

[cottrellnc]

Thanks for replying. I think there is no problem with detection of the hardware. lspci shows me:

01:00.0 VGA compatible controller: ATI Technologies Inc NI Caicos \
[AMD RADEON HD 6450] (prog-if 00 [VGA controller])
...
Kernel driver in use: radeon

Let me describe what I'm seeing a bit more precisely.

1) No problem with the grub menu screen.
2) As soon as the graphical boot sequence starts (the animated logo thingy),
a fast, regular flickering or flashing starts.
3) This continues into the login screen, and continues once I'm logged on and
seeing my desktop. I'm able to access the menu that gives the suspend
option, but it's VERY hard on the eyes.
4) The flickering/flashing goes away totally after a suspend/resume.

I surmise that while the right drivers are being loaded for the video hardware, there's something wrong with the mode in which they're running at first (if that makes any sense). As I mentioned before, with FC 16 on the same box the video was fine from the start.

[Spuck]

Hey, I'm having this exact same problem also! It was really suprising when I accidently clicked suspend and then it fixed the blinking.

I've got the same video card (AMD Radeon HD 6450). It worked fine on fedora 16.

I'm a linux newbie... so I'd love a solution or suggestions if anyone can figure this out. It's just annoying to have to suspend the computer every time I boot up to get rid of the violently flashing screen. Thanks.

[cottrellnc]

Nice to know I'm not alone ;-)

I've now filed a bug on this; see https://bugzilla.redhat.com/show_bug.cgi?id=827895

[jovcek]

Hi, does this help?

http://forums.fedoraforum.org/showthread.php?t=280277

[cottrellnc]

Thanks, but it seems the problem I have is different. The resolution is OK; the issue
is probably that the vesafb driver (built into the fedora 17 kernel) is being engaged
when the radeon kernel module should be used. There's more on this at the bug URL
I posted earlier (#6).

[Screamy]

Yeah, this is a pretty old thread, but I thought this info might save someone a little hair pulling:

I had the exact same problem recently (black screen/tiny flickering margin at top, full-screen video but pale and severely flickering) on Fedora 18, while using a Radeon 6450 PCI-E video card.

I fixed it thusly:

yum install akmod-catalyst

reboot the system, then as root, rebuild initramfs (backing up the old img first):

mv /boot/initramfs-$(uname -r).img /boot/initramfs-$(uname -r)-radeon.img
dracut /boot/initramfs-$(uname -r).img $(uname -r)