Recently I replaced my 6 years old system with one better suited to modern game requirements.

I have no issues running Witcher 2 at ultra settings, aside from one really annoying problem - at random intervals, the screen goes blank (monitor loses signal from the GPUs), and I can no longer alt-tab or run task manager (which generally helps if an application goes wonky graphics-wise).

Also, during the prologue video, the "Portrayal of a Witcher" or whatnot text also blinks for a split second section of a screen lower a few times. This I can live with, but it seems to indicate some issues the game has with my graphics cards.

I've been running a few new releases at highest settings, and this is the first time I encounter such an issue, making me suspect overheating is not the cause. I don't really have the time to run tests to check that, especially since only Witcher 2 is affected.

I have noticed that there are reported issues with the ATI cards (I have a Crossfire setup of 2 Radeons 6870s), but no details are given. This problem occurred on both the 11.6 and 11.7 Catalyst drivers

tl;dr version:
Is there an awareness of an issue with ATI Radeon 6800 series running Crossfire for driver release 11.6 and 11.7 that would cause the Witcher 2 to lose synch with the monitor (or stop sending instructions to the graphic cards)?

Also, for the love of His Noodliness, please provide at least higher resolution font. Scaling other interface elements to the screen res would also be helpful, but right now it's the tiny font that's killing my eyes.

Crossfire / SLI is imho the number one suspect when something like that happens. It's not your fault, many games have problems with multiple graphic card configurations.

To cut it short: Does it work when you disable Crossfire, running it on just one card?

Hi. Godzilla beat me to it as i was going to suggest trying it with one card. It should do fine on a single 6870 as it ran well on the 5770 I had in here.

Appreciate the replies.

While I generally do not have the time to tinker too much, I'll see what happens.

I identified a point where this happens 3 times out of 3 tries - during the cutscene with Foltest and the two brats, right after "One day you will be king, and kings do not weep, Boussy" or whatnot.

In all three attempts right after this is said the screen went blank. I'll see what happens without Crossfire... though I'm a bit put off by having to cut my system's rendering capability that way.

I understand this to be either hardware, or, more likely, software issue, but at this point it should have been resolved. Given that this does not occur with other games I play, it appears to be related to some quirk of Witcher 2 engine, rather than a general driver issue.

In any case, thanks for the suggestions. I'll see what happens, though I'd rather get some downtime than deal with computer issues right now :)

Yeah, like I said, not your fault, and for the most part not the driver either. Though solving problems like this is usually up both to the game developer and to the graphic card developer, or I should better say it's in the interest of both. Who solves the problem in the end...for the customer its not important, the main thing is its solved.

Anyway..what I and others suggested is a workaround at best, not a solution. I don't know if you ever had a dual graphic card setup before (with your old system), but I guess I should give you the friendly advice to expect problems like this in the future. They're quite common as far as I know (someone please correct me if I got the wrong impression). ;)

Sure, it would be best if those problems were solved for good. Unfortunately often times that's simply not happening. In this singular case you should get more than okay fps with a single card so it's not a big deal in my opinion. And it's the best you can do for now I'm afraid...

Damn, knowing that you miss out on this great game almost makes my heart break. :D ;)

Anyway, don't forget to mark the topic solved.

Do you have the latest profile from AMD?

I sometimes get this problem as well, and I only have 1 graphics card. It happens mostly doing cut scenes, but it seems to happen alot less frequently, when I lowered a few settings. When it happens the screen goes black and my monitor goes into Power Saving, and I have to restart to computer.
I actually have a Radeon 6870 card as well, and I believe there is a small graphics card in my motherboard, but it isn't running.

Now there's an idea. I'll have to check it after work tomorrow, but thanks!

Will keep this open till either give up on trying to find a solution (probably won't take long, I don't have all that much free time), or somebody actually throws out a solution that works.

Yourself, do you also get problems with proper display for the non-rendered cutscenes (intro and the death of Geralt recollection)? On my system there's a lot of flickering "shadows" of whatever is being shown... If so, sounds like a problem with the whole line of the 6870s.

Are you forcing anything via Catalyst Control Center?

Make sure it's all set to "Application Controlled".

I only have a 4890 with v11.4, but I don't have any graphics issues whatsoever.

As far as I could determine, everything is indeed "Application Controlled"

I also installed AMD newest game profiles, though frankly I gave up on trying to figure out how to make sure one is loaded. From what I could find after brief googling, they load automatically, though I'm rather uncertain whether that is accurate...

Would appreciate somebody more knowledgeable correcting me if that is not the case.

Unfortunately, it seems that until CD Projekt releases a patch fixing the issue with Crossfire (or, possibly, the Radeon 6800 series, based on Yourself's comment), I have the option of either playing on a single card and hope this does not occur (didn't have time to test this yet), or not play at all.

Even if the game did run on one card (at lower settings), I think I'll wait for the patch just for the sake of the eye candy.

I do hope they are working on this issue. So far they are ahead of everybody else in my books based on the support Witcher 1 received. Frankly, I bought Witcher 2 at full price mainly to support the developer. I learned quite a while ago to wait half a year or more with a purchase to avoid being a paying beta tester, or receiving only a part of the game at full price (looking at you, EA...).

Anyway, looks like the originally reported issue is here to stay for now. Le sigh.