7950 - "Artifacting" on secondary display

[Mabu]

I'm having an issue with my 7950 when using a second display in clone mode, where the secondary display constantly produces what appears to be artifacts. The most notable of this is an almost constant screen-tear-like effect on anything in motion (video, games, even scrolling in a browser, etc), very much akin to normal screen-tearing when not using vsync. However, it's a little bit different than normal tearing, since the tearing always occurs in the same location on the screen. There are other issues as well, such as the image "shaking" at times, as well as the display sometimes losing the connection/gaining the connection back in rapid succession.

My primary display (Dell U2311H) is connected via a Mini-DP -> DP cable, and I've tried all manner of connections on the secondary display (Samsung LNT4061 TV), including straight HDMI, DVI -> HDMI cable, and Mini-DP -> HDMI adapter + cable, all with the same effect. I've also tried running the output from the card into my Denon AVR with those same different cables, which then outputs to the TV, and still get the same results. That eliminates any bad cables.

Should also mention that the issue is not with the TV itself, since I can set that as the primary display, and then get the same errors on the Dell monitor with it being the secondary display. And if I use only the TV by itself as the sole display, everything is perfectly fine.

I've also tried a number of different drivers (currently using 13.3beta), and no luck there either. The closest thread that I can find with a similar is issue is here, but I am not running Eyefinity and have tried using both Mini-DP connections on the card (which was the apparent fix found in that thread).

Anyone else having this issue, or able to provide some advice or other possible fixes?

 

[djsb]

Changing the vram clock speed produces artifacts that sound like what you're describing (i.e. artifacting on just a secondary screen and the primary). Can you run GPU-Z while it's happening and report whether or not the memory speed is changing?

Also can you try changing the primary monitor so both of them are running on DVI or HDMI? (I've heard of issues resulting from mixed outputs, but have never seen them myself.)

 

[Mabu]

Yeah, I'll fire up GPU-Z when I return home from work this evening and check on the vram clock speeds.

The card has 4 outputs: 2x mini-DP, 1x dual-link DVI, and 1x HDMI, so I won't be able to do two connections of the same exact type except mini-DP. I have always been using at least one of the mini-DP ports, that which has been going to the primary display (Dell monitor). As I haven't done it yet, I'll certainly try connecting the monitor with straight DVI, and the TV with straight HDMI.

Thanks for those tips, and I'll report back to see how it goes.

 

[Fooshnik]

Check the FPS of the TV on FRAPS. I had issues with one system where it would detect one display as 60Hz and the other as 120, even though both were 60. I ended up runing one display off the IGP.

 

[Tradio]

also if u havent, use the new AMD gpu driver uninstallation program and reinstall the latest

 

[Mabu]

Well, right off the bat, I can confirm that the issue is somehow related to using either of the mini-DP outputs on the card. As soon as I connected both displays using the HDMI output for one and the DVI output for the other, the issue went away.

Here are some very quick GPU-Z readings after watching about 2 minutes worth of a video in WMP:

1. HDMI + DVI

Everything here looks pretty normal.

2. HDMI + Mini-DP

In this config, I was getting the tearing on the secondary display.

Notice a couple of spikes there at the beginning in just about everything, and the odd graphical readings of Core Clock.

Still more testing to do, but this at least confirms it to be an issue with using the Mini-DP outputs.

 

[tropico]

Have you already tried the 12.8 drivers? I was having the same problem with the 13.1 drivers recently and rolling back to 12.8 completely solved the problem.

 

[suiken_2mieu]

There is an issue with cloning dp and non-dp displays on amd cards. Dp runs at exactly 60hz whereas dvi / hdmi tends to run ~59.985Hz, so you get this tearing effect. This is due to being off sync.

 

[Mabu]

There is an issue with cloning dp and non-dp displays on amd cards. Dp runs at exactly 60hz whereas dvi / hdmi tends to run ~59.985Hz, so you get this tearing effect. This is due to being off sync.

Interesting. I had a 5850 before the 7950, and never had the issue at all, so I'm guessing it's exclusive to the 7xxx series?

Also, I'm still a bit confused why I'd see the issue when using both of the DP outputs simultaneously. Are you saying that if I had two actual DP displays that there would be no issue? Currently, I'm using a passive DP->HDMI adapter to connect the TV. Is it because the TV isn't an actual DP display? EDID somehow involved here?

 

[suiken_2mieu]

Interesting. I had a 5850 before the 7950, and never had the issue at all, so I'm guessing it's exclusive to the 7xxx series?

Also, I'm still a bit confused why I'd see the issue when using both of the DP outputs simultaneously. Are you saying that if I had two actual DP displays that there would be no issue? Currently, I'm using a passive DP->HDMI adapter to connect the TV. Is it because the TV isn't an actual DP display? EDID somehow involved here?

It's possible to happen on to DP displays if the edid shows different timings for both displays (which would most likely would happen with two different displays). You may be able to fix it with a EDID override (try ToastyX's CRU.exe).

Also, I've seen this on my 5870 Eyefinity 6 Edition, so I don't think it's exclusive to the newer series.