I am getting flicker in most of the games I am playing (but not all), it is in the form of horizontal lines flicking up and down the screen. While it isn't hugely noticable, it is getting really annoying. I have tried virtually every solution I can find on the internet, including resolutions, refresh rates, v-sync, all options in CCC etc. I have swapped monitors and cables and it still happens with no improvements at all.
I am running a Radeon HD 4890 with Windows 7 64bit.
Now i'm thinking i'm most likely looking at a faulty graphics card, but I also wonder whether it may be my PSU, as it's not a well-known brand (800w though).
are you using the 10.6 drivers? ive had problems with that one my self for my 4850 but i switched back to the 10.4 drivers by uninstalling the 10.6 and installing the 10.4 drivers, try it, it worked for me so it should for you as well, here's a link for the old drivers :
My brother's PC is literally right next to mine and we have the exactly the same monitor. I fixed my rig up to his cables and monitor and I have the same problem. I then tried my card in his PC (had to route my PCI-E power cables from my rig to power it) - same problem. I figure it's a faulty card.
I order a new card (5750) and get exactly the same problem, RMA it. Next I get a new, better PSU thinking the card must not be getting the power it needs - doesn't help.
Now there's only a few things I can think of; the monitors (as they're the same model), interference coming from somewhere in my house or the DVI-VGA adapter I have to use with my card. I tried the adapter with my brothers setup, he's still fine. I then literally turned off absolutely everything in the house except my setup - still the problem persists.
Then I get an old crappy viewsonic lcd monitor out and try it - yes, still there.
Now, the funny thing is when I hook my rig up to my 37" LCD TV via DVI-HDMI adapter I can't see the flicker at all in the same games.
I'm so confused right now and i've spent so much time trying to fix this. Any more suggestions?