New install of LinuxCNC mutliple issues

I am new to Linux as you will see. I just installed Linuxcnc to my old desktop with an Intel Core 2 Duo 2.4 GHz E6600, 4GB ram, Nvidia GeForce 9800GT 1GB. I have a few issues.

1. Right off the bat I was able to update Linuxcnc using the Update Manager. Now it says I have 89 updates available and when I click "Install updates" it states "zero updates applied, there are 89 more updates available.

2. I have no idea how to see the video card installed or its driver. I tried running the command lspci | grep vga and it returned nothing but the same command prompt I started with.

3. I currently have 60,000ish latency and would like to bring that down. Based on reading I believe a good place to start is the video card. Next i would like to isolate the cores but when I attempt to edit the file at etc/default/grub and then save it it states that it "cannot open the file to write"


Sorry for being hopelessly lost. I have spent all day trying to figure this out on my own but have not gained much ground.

1) I don't use synaptic. In a terminal
sudo apt-get update && sudo apt-get dist upgrade

2) sudo lspci -k will show the driver module in use for each, it will probably be nouveau
If your card has on-board video, remove the card, change BIOS to use the on-board chip and try that

3) Just general Linux newbieness
Try reading forum.linuxcnc.org/forum/18-computer/15256-linux-tips, you should see why you can't open it unless you use sudo

regards

Thank you for the help. I was able to get the update using the synaptic packet manager. But I will use the terminal code in the future. The driver is the nouveau. Am I correct in understanding that it automatically loads default drivers when a new card is installed? I do not have on board video and the only other card I have is an Nvidia GT8600 256MB. I installed it and did not get much better results. I read through the linux tips. Does the root password change still apply or was that addressed in an update?

As for the latency I was able to get it down to the 45000 mark with 1 glxgears, surfing and running an irq watch . I was able to isolate the core, and also followed this thread for the same processor I have. I was able to edit the grub files by following this thread and using Kent Reed's 07_rtai file but modified the instances of "isolcpus=1" to "isolcpus=1 acpi_irq_nobalance noirqbalance" and installing the other files in the first thread I mentioned. I am not getting the results that are posted there however. Overall I think I am getting the hang of this, taking lots of notes.

In closing I plan to get a ATI graphics card to see if that will remedy the current issue on this pc. If not I think I will follow this build thread here . My last question is how much does old and worn out compenents play into latency? My current setup is the families old desktop and was used alot. Would the exact same components new off the shelf perform better than the old ones?

Thank you for the time and help.

Goi

All nvidia cards are best avoided.
BTW Don't ever install the proprietary nvidia drivers, things will get much worse.

Does the root password change still apply or was that addressed in an update?

It is still valid if you have that problem, if sudo works there is no need.

In closing I plan to get a ATI graphics card to see if that will remedy the current issue on this pc

Newer ATI cards may not work much better either
Look here wiki.linuxcnc.org/cgi-bin/wiki.pl?Latency-Test and try to find a card mentioned.
The good news is that you will probably find they are only available second hand on ebay, so cheap.

Would the exact same components new off the shelf perform better than the old ones?

The components either work or not, there is a base limit dependent upon the machine, BIOS etc, some are just better than others.
I would stick with what you have and try a cheap older ATI / Radeon video card for now.

Thank you for all the help. I have two Radeon X300SE coming from ebay ($23). Following one of the builds from the list you linked I may upgrade my processor from the Core 2 E6600 to the E8400. This would make my build almost identical to one of those on the list and its only $17 for a new one, from what I can tell the single thread processing on the higher end one is much butter. That would leave just the mother board. Following the build from the list I could use a Gigabyte P35-DS4 but it doesn't leave me with an option for on board video. In all this can be built for under $100 right now.

Just take it piece by piece for now and hopefully I can get latency under 20000 which would be just fine for my needs.

Thanks again.

I may upgrade my processor from the Core 2 E6600 to the E8400. This would make my build almost identical to one of those on the list and its only $17 for a new one, .....
That would leave just the mother board. Following the build from the list I could use a Gigabyte P35-DS4 but it doesn't leave me with an option for on board video. In all this can be built for under $100 right now.

Intel Core 2 Duo PCs can be bought for peanuts, they are obviously the current wave of corporate desktops that are getting upgraded.

I would not bother buying parts, they cost more than the computer is worth.
You could get a complete computer for $20
www.ebay.com/sch/i.html?_from=R40&_trksi...Duo+Desktop&_sacat=0

If the new video card does not fix latency, put the computer on ebay and buy another computer, repeating if necessary until you find one that works well enough.
Your market seems dominated by Dell and HP, but if you see a Fujitsu Siemens, it would be worth trying, I have had very good latency from them as have others
forum.linuxcnc.org/forum/18-computer/309...atency-i-came-across

regards

Got the video cards today. Installed the first one and did not see a huge improvement. Fortunately it came with 2, as of this writing I am sitting at 17,000 jitter on both threads. 2xglxgears open, playing Brittney Spears video on youtube (figured that was a good torture test) and browsing. First test was around 25,000 but seems to have settled down now and with a reset of the test and opening the different windows we have stayed at 17,000 which is liveable. I should also point out that I am going to use a mesa card and in reading I discovered that the latency issue will not be as big of a deal with this card as I thought it would be. Should I be doing the testing with the mesa card installed?

Should I be doing the testing with the mesa card installed?

No, but all you need worry about is the servo-thread figure. That is what the card is connected to.

That can be 50K or higher max-jitter and work perfectly well