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View Full Version : [g74sx] Color depth reduced, software problem or hardware damage?



Hideaki
12-06-2011, 06:02 PM
I've had my G74sx (3D-Display, geforce 560M with 3GB, one HD replaced with SSD) for about three months now and apart from a few crashes I've had no problems with the current machine, or so I thought.

But today when the BluRay player wouldn't display anything but a black screen I got to wondering about the color depth displayed. A few weeks ago I thought I'd noticed a change in how colors are displayed (various images, including the windows login screen I remembered as 'clean' looking different with less smooth color gradients), but dismissed it as just my imagination.

So I found myself a site with monitor test images (http://www.lagom.nl/lcd-test/) and looked at the gradient section (http://www.lagom.nl/lcd-test/gradient.php). And indeed what was supposed to be smooth showed banding. I changed to 16bit color depth and back to 32bit with no change. Then I went back to the latest nVidia reference driver rather than the beta driver I'd been using and it got better, but still not completely smooth (of course, it might have been the reboot rather than the driver change). The java script info box on that page says my color depth setting is 24bit, not 32bit like I set it in the display properties (1920x1080, 32bit TrueColor, 60Hz).

So now I'm wondering, is there any way to more accurately check this and most importantly determine whether this might be some sort of hardware problem?

dstrakele
12-06-2011, 06:49 PM
What version video driver are you using currently?

Launch NVIDIA Control Panel. In "Display - Adjust desktop color settings", in "2. Choose how color is set", how is it configured for your laptop display?

How is "3. Apply the following enhancements" configured?

In the Video section, "2. How do you make color adjustments", what is the configuration for your system?

Screen shots could be helpful in your answer.

Hideaki
12-06-2011, 07:21 PM
I'm currently using the GeForce 285.62 WHQL driver installed with the 'clean install' option.

Under 'Display - adjust desktop color settings" the "2. Choose how color is set" setting is turned to "Other applications control color settings". ". Apply the following enhancements is set to Digital Vibrance +50%, Hue +0%. Since I haven't changed anything about these I figure they are default settings.

Under "Video - Adjust Video Color settings" it's set to "With the video player settings".

I'll see if I can make screenshots that show what I mean.

dstrakele
12-06-2011, 07:29 PM
That does look like the defaults. I was hoping your settings were different.

Here's another thread on this issue: http://www.asusrog.com/forums/showthread.php?4560-G74SX-screen-issue&highlight=gradient

It'll give you some other things to try, but we were unable to resolve that one.

Are you running the pre-installed Windows 7 OS or have you performed a clean Windows 7 install?

Hideaki
12-07-2011, 01:48 PM
I haven't done a clean install, no. And in the beginning I don't think it was like this.

A few screenshots ...
http://img824.imageshack.us/img824/4103/desktopvsirfanviewsmall.png
I think it's two separate issues. One is that Aero or whatever's doing the desktop background introduces some sort of compression artifacts. Again, I don't think it has always been doing that (I seem to recall first noticing it after a graphics driver crash, but I can't be sure).

http://img337.imageshack.us/img337/1345/greygradientzoomsmall.png
Clear vertical banding here, though that alone might be just a resolution issue of the image used. What's stranger is that every other band looks like it has a sort of grid pattern in it. No matter how much I zoom in the grid size still remains the same though, so it's not part of the image. It's like the monitor can't display the color exactly so it uses some sort of dithering? I see the same effect in some of the colors in the previous image as well.

http://img33.imageshack.us/img33/7162/screenshotsmall.png
The color transitions in this screenshot aren't always smooth and I think it's the same grid pattern effect in some of the colors that makes it noticeable.

Hideaki
12-07-2011, 01:49 PM
http://img855.imageshack.us/img855/565/videoc.png
The effect is especially pronounced here, with a pattern of horizontal bands showing that pixel grid.

http://img705.imageshack.us/img705/7942/lcdtestsmall.png
Finally this bit of JavaScript claims that color depth is set to 24bits when the control panel says 32bits.
http://img33.imageshack.us/img33/9459/controlpaneljt.png

Hence my question about how to check this for certain. If something screwed up the color depth setting I could imagine that leading to this sort of effect, but I don't really trust either windows or some random script to tell me the whole truth.

JRd1st
12-07-2011, 02:49 PM
Do you trust Adobe?

Here's what I get for color in Photoshop CS5 info - Video Mode: 1920 x 1080 x 4294967296 colors

MPerni
12-07-2011, 03:10 PM
As i remember 24 and 32 bits are the same... Just that 32 bits also have alpha or transparency, but you will have the same colors.
You are having that banding issue with all the images?? Check this ones, the first one is made with 8 bit, im not seeing lines in that one, and the second one is made with 16bit, there i see the lines http://www.megaupload.com/?d=GIK1UGNX
Really donīt know why this happens, but i see this "problem" in my other pc, in the external monitor, everywhere, even in the television in some chanels. But i remember that if i add like 0,1 of noise to the gradient layer (when iīm working in ps or il) that problem of banding goes away, donīt know why!!

dstrakele
12-07-2011, 05:11 PM
In the "List All Modes" screenshot, there is a "True Color (32-bit) 59 hz setting. Have you tried this?

Hideaki
12-07-2011, 05:37 PM
I don't have photoshop but I'll see if I can get it.

I don't see any real banding in the first image, MPerni, but I do in the second. This strange grid effect does appear in both, though, if only very, very discreetly in the first.

I've tried the 59Hz setting and the 100 and the 120, but saw no difference (except that 100+ Hz leads to occasional flashes of visual artifacts).

I also tried booting from an Ubuntu live system cd to see if it was a windows issue, but I'm not entirely sure how to interpret the results. I didn't get this grid effect there, but I'm not entirely sure what color depth settings it used. Under windows if I go back to 16bit the grid pattern effect disappears as well.

380mcn
12-08-2011, 05:18 PM
isn't the intel DSPT control option ON?

Hideaki
12-08-2011, 10:35 PM
DSPT is only set to on in the Battery Saving mode on battery, off for all other Power4Gear profiles. How could DSPT cause something like this?

Update: I experimented with different drivers a bit, using the 'clean install' option every time and now I'm back at the 290.36 beta driver. Somewhere along the line the grid pattern effect thing seems to have disappeared - confirming it as a software problem to my mind - but now when I look at an image or a video that previously showed these patterns there's a noticeable flickering of the screen in that area.

Increasing the refresh rate to above 100 Hz seems to mostly do away with that, but it also means that I get a flashes of visual artifacts every 10-20 seconds or so (which I always have when using the stereoscopic 3d and switch to 120Hz for that). Now I have to decide whether to suffer flickering or artifacts, which is only a slight improvement :(.

JRd1st
12-08-2011, 10:39 PM
RMA it. You never know when something like this is the harbinger of total failure.

380mcn
12-09-2011, 11:50 PM
DSPT is only set to on in the Battery Saving mode on battery, off for all other Power4Gear profiles. How could DSPT cause something like this?

Update: I experimented with different drivers a bit, using the 'clean install' option every time and now I'm back at the 290.36 beta driver. Somewhere along the line the grid pattern effect thing seems to have disappeared - confirming it as a software problem to my mind - but now when I look at an image or a video that previously showed these patterns there's a noticeable flickering of the screen in that area.

Increasing the refresh rate to above 100 Hz seems to mostly do away with that, but it also means that I get a flashes of visual artifacts every 10-20 seconds or so (which I always have when using the stereoscopic 3d and switch to 120Hz for that). Now I have to decide whether to suffer flickering or artifacts, which is only a slight improvement :(.

It is well explained on this forum how intel DSPT in fact reduces color bit, i'm not going to explain again.
but with this extra info of yours is clear to me that you need to RMA it ASAP.
greetings

Hideaki
12-10-2011, 12:30 AM
Not what I wanted to hear at all :(. Despite various initial problems I'd been pretty happy with this machine until now. But I guess I have to look up how that works with the local Asus people.

Especially since the fresh and clean install I did today didn't change anything. The 290.36 driver gives the flickering, the older ones the grid pattern. This sucks.