problems with xorg.conf solution for nvidia

I posted a similar threas on another forum, just in case it looks familiar.
I'm trying to run linuxcnc on my computer which has nvidia card, so naturally I get very high latency values, spikes of up to 450000 just opening Firefox or glxgears. No problem opening small games, playing music, installing programs, moving files around, etc. Once Firefox or glxgears are open, latency stays in the 5000 - 16000 range. So I tried running the xorg.conf modify (using nv instead of nvidia) suggested in the wiki and latency went down to 16000 even when opening firefox.

But now I can't run glxgears, and get the following error message:

Xlib: extension "GLX" missing on display ":0.0".
Error: couldn't get an RGB, Double-buffered visual

And most importantly, I CAN'T OPEN MY-MILL EITHER! I get a huge error message but can't find a way to copy it into a text file, it won't allow right-click copy or ctrl-c. So I attach a modified image of the error message, that's all I could do. Sorry.

Any ideas on this? The error seems to have something to do with GLX files.

By the way, I run in a dual boot system with Windows XP. A better solution would be to get a "new" old computer, but how can I be sure that they will work? I just don't want to spend any money in something that "might" work.
My options are:
1) P4 2.6 Ghz, 512 MB RAM, 40 GB Hard, seller doesn't have much specs about it (video card, etc),
2) IBM 8189 P4 3.0 Ghz, 1 GB RAM, 40 GB Hard, specs can be found online, seems to have integrated video card too, an Intel 865G. Doesn't appear in the tested hardware listed the wiki page.
3) IBM 8414 P4 3.0 Ghz, 1 GB RAM, 40 GB Hard, can't find specs either.

Thanks for any help you can provide, specially on the xorg.cong issue.

Hi

Google 'Xlib: extension "GLX" missing on display ":0.0"' and look at the Ubuntu forums threads

I immediately found 3 that reported the same problem and in each case it came down to elements of the drivers for the proprietory nvidea drivers still being loaded and interfering with the new driver.

You need to post your /var/log/dmsg entries for the error which is actually causing the failure to start, but doubtless it will be GLX dependent, as Axis relies heavily on openGL.

I would try and fix this first, a new PC is just a 'pig in a poke' if you have no idea what is actually in it.

2) IBM 8189 P4 3.0 Ghz, 1 GB RAM, 40 GB Hard, specs can be found online, seems to have integrated video card too, an Intel 865G. Doesn't appear in the tested hardware listed the wiki page.

I think this might actually be the 82865G graphics chip, in which case I have 3 computers which use it and it runs no problem.

However persevere with this one, should just be a case of locating the libraries / drivers which are still getting loaded and deleting them.
Could be as simple as going through Package Manager and 'completely removing' previously installed the nvidea non-free drivers, if that is where they originate.

regards

Well, while I waited for an answer yesterday I tried the "vesa" option (I just couldn't stay still) and everything went wrong from there, up until a few minutes ago when I had to reinstall ubuntu! So I formatted the ubuntu partition and started from zero and now I can't find the xorg.conf file, but latency results are down in the 10000-12000 range. On my first run it spiked up to 250000 for some reason but on my second run which has been running for about 25min it has been at around 12000, with 6 glxgears windows running, firefox, sm media player and some software installs, so I guess something is better now.
Just something different I did this time: did not install the nvidia drivers when I was asked to, so non of their components are present.
I do have some display issues with letters in firefox showing incomplete, guess it's due to the fact I haven't specified a driver, so I will do some research about this and play around and see if the latency stays low.
So this seems to be going well after all and just in case, sounds like the IBM would be an option, and the vendor even agreed to let me install ubuntu and run the test before committing to buy it.

Still, I wonder why the xorg.conf file is not present. Thanks for your help. Have a great day.

Hi

Glad you are making progress

Still, I wonder why the xorg.conf file is not present

I updated the wiki some while back to cover the steps necessary to create an xorg.conf file in more depth
wiki.linuxcnc.org/cgi-bin/wiki.pl?Troubl...oting#Display_Issues

10.04 and above do not use it by default, but will read it if present.

On my first run it spiked up to 250000 for some reason

This can happen at start up and never re-occur, PCW reported several instances of this.
You need to verify this by running a long latency test however, because only the first incident of a real time error will be reported by Linuxcnc.

One thing to check is whether it occurred when you moved the mouse and if so was it a USB mouse?
I had high spikes on one machine which disappeared when I substituted a PS2 mouse for the USB one

regards

Hi guys, thanks for all the help and advice, I finally hooked up my machine and did a couple "jogging" movements. Everything working fine now, just some fine tuning on the mechanics before running actual gcode.

As far as ArcEyes' suggestions:

I updated the wiki some while back to cover the steps necessary to create an xorg.conf file in more depth
wiki.linuxcnc.org/cgi-bin/wiki.pl?Troubl...oting#Display_Issues

10.04 and above do not use it by default, but will read it if present.

I will try this later, as it seems the graphics are working fine for what I need right now, but as I get more used to Ubuntu I try fixing it better. Still don't understand why it was present in my first install and not in the second. Maybe it has to do with having installed the nvidia drivers?

One thing to check is whether it occurred when you moved the mouse and if so was it a USB mouse?
I had high spikes on one machine which disappeared when I substituted a PS2 mouse for the USB one

The mouse is actually USB, so I will just run a longer test as soon as I can and see if something like this repeats again and if it does I will will pay more attention as to how and when it happens, and research or post again for solutions.

Thanks again for all the help, have a great day.

Alfredo.

cletero wrote:

I finally hooked up my machine and did a couple "jogging" movements. Everything working fine now,

Looks like you are on your way

Still don't understand why it was present in my first install and not in the second. Maybe it has to do with having installed the nvidia drivers?

When you have nothing better to do on a wet weekend, try googling 'ubuntu auto detection with HAL' or similar.
Starting at 9.04, Ubuntu went over to automatic hardware detection. This works fine if you have new hardware, if not it can cause problems, monitors stuck in low resolution etc etc.

You are right, when you initially installed you would have had a default detected setup, with probably the open source generic nv driver loaded.
Because you then selected the non-free nvidea drivers that cannot be distributed with Ubuntu, the setup would probably have created an xorg.conf then to install them.

regards