Hi all!

More of a puzzle than a real problem, since I'm in the middle of preparing a new installation. I have a long in the tooth Fedora 15 installation on a workhorse machine. Using the proprietary 295.59 driver and a GeForce 9500GT card. There's been no software changes whatsoever during the last few years, yet some very noticeable horizontal tearing reared its ugly head during the last week.

I've tried tweaking all the user-friendly options once can tweak in nvcontrol. Tried specifically setting the resolution to 1920x1080 at 60Hz instead of auto.

The tearing is not limited to opengl or XVideo. There don't seem to be decoding or performance issues in either 2D or 3D. I've been testing out the system with Quake4 since I set it up, and it's just as good as it was on its first day. Rather, it's an omnipresent X thing. It's mostly noticeable with low-frame gifs, for example.

What really irks me is that I cannot pinpoint a specific even which might have caused it. It's very frustrating to have 1080 video playing smoothly, with no tear cause of performance issues, but have very weird, over-all tearing.

Any ideas?

You are behind a few releases on that driver it's now at 340.32 at Nvidia site & I'm quite sure that debian(my OS) isn't far behind. Not sure about Fedora.

I'm a few solid releases behind, yep. The thing is, the problem appeared just recently. The rig worked fine for several years before this popped up a few weeks ago. The driver blob has not been touched at all.

I'm surprised that you haven't experienced sooner but Fedora is similar to RH. Not sure if Fedora pushes updates like Debian , but in Debian it's almost a must to update because a simple dist-upgrade can leave system broken.

Also Fedora support doesn't last long, it's been unsupported since 2012.
Time to upgrade, the current version is 21 & support is only approx 6 mos.
Since you're familiar with RedHat type OS you might consider CentOS, which has LTS(Long Term Support).

I'm aware that the setup is ancient. I will upgrading this machine soon, as I indicated in my original post. It's exactly because this problem is recent, that I posted in the first place. I figured it could be interesting to figure it out.

The newer version of Nvidia may not work with your current system,because if it requires upgrade of Xorg or any other package it may not be available.

Once again. I know it won't . My original query was addressed to people who might have an idea as to why this issue would pop up now with the current driver and system after not having been present previously. Thanks.

Possibly a hardware fault? Video memory or the chipset itself?

There's no drop in OpenGL performance and change in temperature in both idle and high performance mode. I wonder if there's an equivalent to Memtest that could be used to benchmark the GPU and memory?

Fedora & CentOS are both live-cd/usb you can try them both & it would be as if you tried all of the tests described. Why not just try them, before installing?

I don't know current video technology well enough to offer much more than the suggestion that it might be hardware related.

But if you are sure that the software has not been changed or updated - or possibly corrupted - that does not leave much more than hardware. As far as the possibility of software corruption, if you have the original Fedora packages backed up it might be worth verifying or reinstalling them (I am not a Fedora user so have no idea how that is handled). If you have a system backup you might compare checksums of driver files, etc.

FWIW - I have one system with an Nvidia GEForce6150SE chipset which has a few quirks. I have tried to diagnose it and used the Nvidia drivers as they have been updated for the past couple of years, and nothing helps. I have decided it is a fault in the silicon as well. It sometimes does some strange things when I start X including artifacts, incomplete rendering and incorrect resolutions. A simple restart of X or reset via xrandr always works and it never recurrs during use... very strange but something I can live with. (In that case I have multiple other machines with the same chipset for comparison, all work OK). The point of this too-long explanation is that not all silicon faults are fatal nor affect performance otherwise - just something to consider...

Going with a live distro might be interesting, yeah. Anything particular you think I should run to test the hardware? If it is indeed a hardware issue, it ought to be tracked down specifically, I would imagine.

Not much comes to mind - but try a live distro and look at some of the graphics that are a problem on the Fedora OS to see if they are any different - watch a video or two... just see if you can come up with a reproducible test case. Of course, with another distro/kernel/footprint/etc there are enough unknowns to make it unavoidably ambiguous at best, unless you get lucky and it reproduces clearly!

Thanks, astrogeek. If things were indeed more severe, I wouldn't think twice about hardware issues. I'll try some alternative distributions. I thought about comparing checksums, but I don't keep any backups on that system. I'm interested to see now whether the same behavior persists with nouveau instead of the proprietary blob. Will post updates after I test things out.

If it works with live-distro without problems you should be fine. If it's a hardware problem then it should expose since it's still running on the hardware but stored in ram.