I installed FC5 about three weeks ago, and have since then had a problem with the graphics: every time my cpu switches to max speed the image on the screen flickers for a frame or two.
My computer is an MSI S270 laptop, graphics card is ATI radeon Xpress 200M, AMD Turion MT-40 CPU.
The CPU switches between 800, 1600, 1800, 2000 & 2200 MHz - the problem only happens when switching to 2200 MHz, no problem what so ever in switching to or between the other frequencies.
I am currently running kernel 2.6.17-1.2174_FC5 64-bit with matching ati fglrx drivers (ver. 8.28.8) from the livna repo, the 3D works without problems (exept for the flicker thing).
What I have done trying to fix the problem:
I have tried the radeon driver that came with FC5 and it gave me the same problem.
Switching to a CPU-speed-switching program other than the default cpuspeed, gives me the same problem.
Choosing to boot the 2.6.15 kernel that is also installed on my system - no problem when switching to 2200MHz, but screen now flickers when changing to 800MHz.
Locking the CPU to one frequency - works, but not exactly the soulution I am looking for.
While trying to fix this problem I read the /var/log/Xorg.0.log -file, which said that my graphics card is detected as RADEON XPRESS 200M (RS480 5955). I found this a little strange as the chipset on my laptop is the RS482 and as such I would think the card should be a RADEON XPRESS 200M (RS482 5975).
I tried forcing Xorg to use the right card by entering ChipId 0x5975 in the Xorg.conf file, which caused Xorg to refuse to start.
A later lspci -v showed that my chipset is detected as
00:00.0 Host bridge: ATI Technologies Inc RS480 Host Bridge (rev 10)
Subsystem: Micro-Star International Co., Ltd. Unknown device 0131
Flags: bus master, 66MHz, medium devsel, latency 0
...which might be the cause of the problem?
I am pretty sure my computer uses the RS482 chipset. Can it be possible that FC has problems detecting it, or that it does not support it (yet?), and can this be the cause of my graphics problem or could there be other things causing the flickering?
While searching for a solution I have found a couple of websites describing the same problem with linux on the S270, so it's not just my computer being faulty either.
All help is welcome