Artifacts while Benchmarking

I'm trying to figure out exactly what artifacts should look like, since I'm in the process of benchmarking and stress testing my sigged P150EM.

I grabbed an unlocked Clevo 680M bios from TechInferno, and I've been steadily increasing the core clocks to find a good stability point.

I tested 720, 760, 800, 840, 850, and 860MHz core clocks without issue, but when I tried 870 I encountered the following:

In 3DMark11, I noticed what looked like a ripple traveling up my screen during Graphics Test 1. I saw one such ripple on my first run and two ripples in succession during my second run, but they didn't show up anywhere else in the benchmark. Are those normal graphical glitches, or artifacts caused by an overclock? They don't look like the glowing blobs, sparkles, or tearing I've seen on Youtube videos taken of artifacting GPUs. Any ideas?

 

Can't really say if there is something like a "normal" glitch. A glitch itself is a sign of something abnormal and if you encounter anything like that, then it is probably not good.

If you are trying to figure out how artifacts should look like... well, they come in many shapes and colours and from your description, that sounds like an artifact.

870Mhz on your card is probably not a stable setup. You should go beyond benchmarking to establish a "stable" OC.

 

An artifact is any sot of graphical glitch, it may look like a blinking texture or something flashing on and off or moving around, but if you lower clock speed and it goes away, and at higher clock speed it comes back, then that's definitely an artifact.

 

It looks like I was mistaken about the graphical issues. I ran 3DMark11 several more times at various clock settings and focused my eyes on the screen each time to maximize my ability to observe any issues. During this process I noticed three different graphical anomalies:

In GPU Test 2, near the end, there's a close-up shot of some coral just after the submarine leaves. After some research, what I saw was slight screen tearing here.
In GPU Test 3, near the end, as soon as the camera swings past the statue you get an extreme close-up of a pillar with animal head designs. A little screen tearing occurs here as well.
In the Combined Test, at the beginning, my screen flashed.

The thing is, I saw all three issues at stock clocks as well as at 860/1800 and 880/1800 overclocks, a result which I confirmed with several runs of the benchmark.

Does screen tearing qualify as seeing artifacts? If so, my card is artifacting at stock settings. How do you recommend I proceed from here?

 

Screen tearing shouldn't be an artifact caused by OCing (though it could be a side effect of higher fps, I guess).

 

You have no idea how relieved that makes me feel. 900/1800 is stable, though the clock throttles a fair bit in GPU Test 1 of 3DMark11, and no other test. That's pushing its benchmark scores down but upon comparing the raw FPS numbers it outperforms 880/1800 in every GPU Test of 3DM11 save GPU Test 1. So long as I don't see throttling in-game, I think a 900MHz core clock should do nicely.

Time to boost the memory!

 

Screen tearing is completely normal, and happens when the frame rate is higher than the refresh rate, it is NOT an artifact.

A screen flash is a little more difficult to analyze, it may even be there on purpose.

 

the artifact i get the most in 3dm11 with my 680m is little yellow squares. They are pretty obvious

 

Run several benchmarks.

Does this occur in games too?

Contact your reseller, this is NOT normal. I would seek assistance ASAP

Those are probably artifacts caused by an overclock. But nothing special.

^^

 

If he's overclocked I don't see what his reseller would do about it. It's probably just his card reaching its limits.

 

Yeah if he is overclocking, then it IS normal.

 

Well now I've learned a fair bit more about this stuff.

I went over to Using your 4GB GTX 680m to its safest and full potential and grabbed the vbios found in the OP there, figuring that something which an experienced user had thoroughly tested ought to work okay on my system.

Enter the artifacts! 3DMark11 ran like a charm but Unigine Heaven 3.0, when maxed out, had texture flickering. Now that I know the difference between screen tearing and legitimate artifacts, I've been able to recognize when the latter are present. One or two building textures will flicker once or twice during each run, and once every couple runs the whole screen will briefly flash some color before returning to the benchmark as if nothing is wrong.

My Unigine settings were as follows: DX11; Extreme Tesselation; High Shaders; 16x Anisotropy; Stereo 3D Disabled; Multi-Monitor Unchecked; 8x Anti-aliasing; Full Screen 1080p

Max temperatures during Unigine runs hit 90C, and the errors occurred most frequently when temperatures were at their highest, though I do recall one flicker at 86C or so, and another near the very beginning of the benchmark.

I need to dial things down a fair bit but I'm not quite sure as to where I should go from here. I guess I can go down to stock voltage and the tried-and-true 854/2200 clocks that everyone seems to run comfortably. I'm curious, though. Are certain kinds of artifacts associated with particular problems? I mean, I've overclocked both the core and the vram fairly extensively. Is texture flickering indicative of an issue with one or the other (vram or core)? Could temperatures be the root of my problems? (ie, if I can reduce them, will the artifacts disappear?) I've used the turbo fans and my Zalman NC2000 set to maximum, but temperatures still hit 90C, which is kind of alarming. I plan to perform the foil mod tomorrow and I'll try once more with the higher clocks before giving up voltage mods for good if things don't go well.

 

HD 7850 Unigine 3.0 flickers - YouTube

YES!

This video describes precisely what I was seeing when I said 'texture flickering.'

What do you guys think?

 

Are you overclocking it? Those look like mild artifacts to me.

 

I was overclocking the card according to a guide I found here:

Using your 4GB GTX 680m to its safest and full potential

Those are the only sort of artifacts I've seen in Heaven 3.0, and the only artifacts I've seen period if my instincts are accurate. Like I said, I would see something like that once or twice per run of the benchmark when it was completed at the absolute maximum settings. Also, it's rarely large chunks like that in my case. Usually it's the texture for a single house that flickers once, rather than a larger portion of the screen.

Now that I've experienced the artifacts for myself I have reflashed the stock 680M vbios (at stock clocks) which I backed up before trying any custom vbios files, and I'll likely sit back and wait until my laptop's cooling can be improved through warranty-friendly mods before boosting things up once more.

I'm guessing artifacts occur due to hot components as well as components not receiving enough voltage to support the clock rates assigned to them. Improved cooling should let me push more voltage into my card to support the higher clocks without artifacting, I'd wager.

EDIT: Just saw a house flicker during a run of Heaven 3.0 at stock (vbios and clocks). The GPU didn't even break 76C...I'm totally lost here. Is it really artifacting? Or is this a driver issue?