8.04 will not power off - Kernel issue?

First post, however I've been lurking for some time...

I am converting a milling machine to CNC and, as a Linux user, the obvious choice is to use LinuxCNC/EMC. I have 2 desktop PCs that I have tested for compatibility. The newest machine is an AMD Athlon 64 3000Mhz with a K8T motherboard and PCI graphics. Latency tests are around the 40K mark, so not ideal. There is also a hardware issue which randomly powers off, so I have decided this machine is a no-go. The second machine is an older AMD Duron 1100Mhz with AGP graphics and latency tests are around 14K with Ubuntu 8.04. The 10.04 version will not boot on this hardware.

So I installed EMC 2.3 using the official Ubuntu 8.04 ISO from this site and then ran through the procedures to upgrade to 2.4 and then LinuxCNC 2.5. The OS starts and runs well, HOWEVER it will not shutdown correctly. It simply halts, turns of the HDD and the CPU fan and PSU continue running until I do a hard shutdown with the power button. I've spent a LOT of hours on the Ubuntu forums and have tried lots of solutions regarding ACPI and APM power management without success. Interestingly, I have tried several versions of Ubuntu, including 8.04 Gnome, 8.04 Xfce, 8.1 Gnome, 9.1 Gnome and they ALL suffer from the same shutdown issue. In contrast, Windows XP, Knoppix and Debian 6 all shutdown as expected. So it seems to be an issue with the 'buntu Kernels rather than a hardware issue.

Can anyone suggest where I go from here? I'd *like* to fix the problem on the original 8.04 install, but now also have Debian 6 installed. If I have to reinstall, preference would go towards a Debian distro but I don't really want the hassle of spending hours compiling kernels and making a customised distro. Is there a LinuxCNC Debian ISO available? Or maybe an easy way to convert Debian 6 to LinuxCNC? There are guides for Debian Lenny but not for Squeeze. I had enough trouble trying to do an offline install of ndiswrapper and wicd in order to get wifi running and don't particularly want to go through that too often.

That was always an issue with 8.04 with RTAI installed.
This version of Ubuntu is now not supported by Ubuntu anymore (no updates), so I just can't see anyone spending a great amount of time on it.

You either live with it or work on getting 10.04 to boot. (which in it's self will be unsupported by Ubuntu this year)

To be clear I'm not saying that linuxcnc is dropping support for 8.04 or 10.04.
8.04 will be dropped when it becomes too much of a hassle to compile new code on it.

Chris M

I assume you have hunted around in the bios for a solution? Personally I would give the other machine another try. I have been running Linuxcnc with very good latency numbers on a similar machine. Mine is: Athlon 64 3000+, 1.5 GB ram, MSI k8n neo 3 motherboard, newer 1 gig nvidia geforce pci-e graphics card (I forget the model). This is with Ubuntu 10.04 and Linuxcnc 2.5, but I have run just about every Ubuntu release over the years on this machine and it has always run well. I have put my 3 axis machine through the paces with 2d and 3d machining without a glitch. If the machine randomly powers off, I would be suspicious of the power supply which is a cheap fix.

OK, so I'm not sure what to do next? I carried out a BIOS upgrade and can get 10.04 LiveCD to boot, although it takes around 10 mins to load up fully. I didn't test latency or start LinuxCNC. I simply did a shutdown from the Gnome menu and again, the PC halted the HDD but left the PSU and CPU fans running.

This leaves me in a bit of a quandary...I have a PC that works perfectly with other OS's but not anything 'buntu flavoured. I haven't used Windows for over 5 years, so don't really want to go down the Mach route but in all fairness, it does look like the easiest solution at present. The only other solution is to buy another PC but I'm obviously reluctant to do that when I already have working hardware...

jaredts wrote:

I assume you have hunted around in the bios for a solution? Personally I would give the other machine another try. I have been running Linuxcnc with very good latency numbers on a similar machine. Mine is: Athlon 64 3000+, 1.5 GB ram, MSI k8n neo 3 motherboard, newer 1 gig nvidia geforce pci-e graphics card (I forget the model). This is with Ubuntu 10.04 and Linuxcnc 2.5, but I have run just about every Ubuntu release over the years on this machine and it has always run well. I have put my 3 axis machine through the paces with 2d and 3d machining without a glitch. If the machine randomly powers off, I would be suspicious of the power supply which is a cheap fix.

I hear what you are saying but I'm a bit skeptical that the mobo is faulty. Long story short, it was retired after the water cooling leaked onto the AGP graphics card and the PC would no longer boot. I didn't spend any time on it when it went wrong as I was already looking at upgrading to the Phenom II Quad core as my desktop machine. I've only recently stripped it and rebuilt (without water cooling!!). Binning the graphics card seemed to be all that was required but I can't help wondering if the mobo was damaged. I tried a couple of PSU's but they had no effect on the random power offs. The CPU heatsink and fan is brand new. I seem to recall having issues when I first bought the machine but can't remember the fix. It was in the BIOS...spread spectrum possibly? It would be nice to get it running as it was a decent machine and has 2GB of Corsair RAM in it.

Out of interest, what sort of latency figures do you get?

Under 5k max jitter. My machine had random power down due to a failing northbridge fan. You might check that if you haven't already. The fans had a bad reputation for failing. I replaced it with an upgraded fan a couple of years ago and never had another problem.

There's no north bridge fan on mine but might be worth retro fitting one. What gfx card are you running? AGP or PCI? I think I'll fire it up again and do a BIOS upgrade and go from there. I might be in touch with you sometime in the future so we can compare notes...

EDIT:
jaredts: would you mind running "sudo lshw >> ~/Desktop/lshw" on your CNC machine and posting the output please?

Likewise - none of my workshop machines turn off completely, it is an issue with that kernel.

The Scroll/Num/Caps lights on the keyboard flash when linux exits, then it is safe to just switch off.

Sorry I haven't gotten back to you, Birchy. I have been a little busy lately and I'm not sure I can get what you have asked for in a reasonable time. If you have specific questions about my hardware I am glad to share. All I can tell you is that I did nothing in the bios or anything special to get this to run well. I don't run a wifi card and have a better graphics card than you do, but other than that the mb is the only big difference.