48x0 Crossfire Display flickering/wavy?

[chaos_being]

I dug up my old post on guru3d from when I was having the same issue for you:

http://forums.guru3d.com/showthread.php?t=206309

In my case, I had pretty much narrowed it down to the dongle creating interference on my crt (I got the flickering every time I had it plugged in, whether crossfire was enabled or not.) Hmm...perhaps the crossfire bridge you are using is a similar source of interference?

The last post on the thread I linked (which was posted several months after I made the thread) is also interesting, pointing at IDE drives being a source of interference as well. Are you running any IDE drives?

[sabrewulf165]

I've tried 3 diff crossfire bridges in every possible configuration you can imagine, and it hasn't made any difference. I'm also really confused by the fact that enabling 16x AA seems to magically fix the problem.

[chaos_being]

Wow, that is weird. Unfortunately increasing AA isn't something that I tried when I had my old crossfire setup.

[sabrewulf165]

Yeah, like I said the only thing I can think of at this point is that somehow the cards (one or both) are rapidly changing between 2D and 3D power states because whatever I'm playing isn't pushing them hard enough, and that this is somehow causing the flicker, but cranking the AA all the way up to 16x taxes them enough to keep them at full power constantly.

Of course we still have to see what happens when I plug in my new PSU this afternoon, but given what I've discovered about AA, I can't imagine how it could be a PSU issue anymore.

[sabrewulf165]

Alright, I'm really at a loss for an explanation now. Got the new power supply installed, and initially it looked like it might have solved the problem, but of course being the paranoid one that I am, I did some play testing at various settings, checking some save points where the flicker had been especially noticeable, etc. Long story short, the problem seems less frequent but more random now. Case in point - I have a save point in one game where I can literally turn 90 degrees to the left, and the flicker is present, turn 90 degrees back to the right, and the flicker is gone. The area where I'm seeing flicker is going 24fps (extremely CPU bound) and when I face right, it's going ~70 fps. Then again I've noticed the problem at 150-300 fps ranges too, so... ugh. Maybe I'll try some of those DVI settings again tonight and see if it helps. And of course just to re-iterate, I'm not seeing the problem at all when 16xAA is enabled, but of course that pretty much negates any performance gain I'm getting with CF in the first place.

[sabrewulf165]

Well just another "maybe" to try tonight - http://www.rage3d.com/Board/showthread.php?t=33865516

I'm not entirely sure but I *think* I have the hotkey poller disabled on my home install, so I'll check that, enable it if it's not already, and see if it makes a difference.

[xMrBunglex]

how big is your monitor? i hope it isn't 1280x1024. if it is, just sell one of your video cards because it isn't necessary at all.

[sabrewulf165]

how big is your monitor? i hope it isn't 1280x1024. if it is, just sell one of your video cards because it isn't necessary at all.

Do you feel better now? I plan on investing in a larger display, but certainly not until I can be satisfied that the problems I'm experiencing can be worked out. Thanks for your input though.

For anyone following the subject of this thread, Hotkey Poller (aka External Event Monitor) doesn't seem to make any difference.

[sabrewulf165]

Still no solution and the only reliable workaround so far is enabling 16x Box AA, which of course saps quite a bit of performance.

[sabrewulf165]

bump

apparently I am not alone - http://www.rage3d.com/BOARD/showthread.php?t=33928403

[perkam]

Could you make a post with a list of all the things you've tried till now, sabre?

Perkam

[sabrewulf165]

Could you make a post with a list of all the things you've tried till now, sabre?

Perkam

Good call. I'll add this to my original post as well:

So far I've tried:

-one bridge vs two, swapping bridges, diff connectors
-vsync, refresh rate, in-game fps caps, etc.
-various CCC settings including Cat. AI and DVI frequency/alternate
-enable/disable hotkey poller/external event util
-set mobo PCIe to 101 instead of 100
-diff ports on the card
-diff dvi cable
-dvi/vga adapter
-diff monitor
-diff cards (borrowed a third 4850 for this purpose)
-diff drivers (have tried them all at this point)
-fresh install of XP, drivers, and games

[perkam]

Good call. I'll add this to my original post as well:

So far I've tried:

-one bridge vs two, swapping bridges, diff connectors
-vsync, refresh rate, in-game fps caps, etc.
-various CCC settings including Cat. AI and DVI frequency/alternate
-enable/disable hotkey poller/external event util
-set mobo PCIe to 101 instead of 100
-diff ports on the card
-diff dvi cable
-dvi/vga adapter
-diff monitor
-diff cards (borrowed a third 4850 for this purpose)
-diff drivers (have tried them all at this point)

Then i guess it should be standard procedure what your next step should be.

New Install of Vista + New Install of Drivers + New install of games.

Hopefully you'll only have to do it this once

Perkam

[sabrewulf165]

Then i guess it should be standard procedure what your next step should be.

New Install of Vista + New Install of Drivers + New install of games.

Hopefully you'll only have to do it this once

Perkam

Ah, I suppose I should add "I already tried a fresh install of XP and got the same issue" to the list.

[demowhc]

try disabling crossfire and make sure each card has the same gamma and colour settings... swap the monitor over to the second card if you need to check it has the same settings..

[xMrBunglex]

just turn CrossFire off until you get a bigger monitor. i'm not trying to be a monitor snob or anything. it's just that CrossFire can offer negative scaling in low resolutions when the cards aren't being stressed. it's possible you're even getting interference from PowerPlay at a low resolution.

all i'm trying to say is that you should get high frames from a single card on most every game if you're running a 19" monitor. don't turn CF on if it isn't needed.

[Kondik]

Yes pretending that the sun isn't upon our heads is an option but wait ... you will still get your skin sunburned.
The way of the Lazy Badger or pretend that there is no problem Isn't the best way I think, he bought 2 VGA's , if he didn't wanted to go CF he wouldn't buy them whould he ...

sabrewulf165

Can you test those card's in someone's else PC ? If he won't have any issues running them it's MOBO,PSU or something problem, will find it eventualy.

[sabrewulf165]

just turn CrossFire off until you get a bigger monitor. i'm not trying to be a monitor snob or anything. it's just that CrossFire can offer negative scaling in low resolutions when the cards aren't being stressed. it's possible you're even getting interference from PowerPlay at a low resolution.

all i'm trying to say is that you should get high frames from a single card on most every game if you're running a 19" monitor. don't turn CF on if it isn't needed.

It's cool, I wasn't trying to be a jerk, just frustrated. And the classic powerplay bug is definitely something I considered, but how do I tell if that's what it is, and how do I disable powerplay or fix it if that is the problem?

Also, for what it's worth, the "The way it's meant to be played" Intro to UT2k4 is a perfect easily reproducible example of when this problem is easily spotted. As soon as the character starts to smash through the nvidia logo, the screen flicker starts going crazy.

And no I'm not using CF to play UT2k4 it's just a good example of when the bug is noticeable

[sabrewulf165]

Reset all of the CCC settings on both cards to factory defaults, no difference.

And setting 16xAA still fixes the problem flawlessly. It's the only thing that has worked so far. Dammit.

[perkam]

Have you tried clocking the proccy back to stock, as well as the ram?

Perkam

[sabrewulf165]

Have you tried clocking the proccy back to stock, as well as the ram?

Perkam

Yeah, tried disabling spread spectrums too (I dunno, maybe it generates interference or something )

[sabrewulf165]

bump, anybody else got ideas or made any progress? Forcing triple-buffered vsync "helps" for me, but only because it generally keeps my framerate in the "safe" non-flicker range. I'd really like to find a fix or at least a more useable permanent solution (only other idea I've heard is connect via HDMI, but that doesn't help much if my display doesn't have an HDMI connector)

[EniGmA1987]

Could you try Edge-Detect AA mode? See if the problem still comes up in that mode when you drop down to lower settings.

[sabrewulf165]

What do you mean by "lower settings?"

And yeah 8x with ED is the mode I was using when I originally noticed the problem. Both 4xED and 8xED exhibit the issue.

[demowhc]

that is really odd.. ED only makes my AA quality improved with no side effects (other than lower performance..)