13. Frequently Asked Questions

13.1. How do I add shared library files?

Linux makes extensive use of shared library files. These files are typically stored in /lib, but additional libraries might be stored in other directories. The file /etc/ld.so.conf lists the directories that contain shared library files.

When you compile and install from source, the install program often copies the new shared library files to /usr/local/lib. However some distributions do not include this directory in /etc/ld.so.conf. So you must add the directory. Just use a text editor and add /usr/local/lib to the end of the file. Save and close the file then use the ldconfig command to register your changes. You do not need to reboot the computer.

13.2. Is the C3 Pentium compatible?

Yes. But Samuel 2, Ezra, Ezra T C3 processors have a problem with the cmpxchg8b (i.e. CMOV) opcode. Nehemiah and Antaur processors are not affected.

The identification issue is that the C3 is identifying itself as 686. According to the Intel IA32 documentation, this is correct: C3 does not implement conditional moves*, and do not pretend to implement conditional moves. The Intel documentation states that you should check before doing conditional moves, and that cmov implementation in the processor is optional. The GNU compiler people have assumed that all 686's implement cmov's, so code compiled for the i686 architecture may not execute on the C3. Code generated by GCC does not check for these optional features as the intel documentation says you should. When downloading binaries for the C3, don't go higher than the i586 level. When building, you may want to target the 586 or even the 486, because of the way the C3 is built internally: It's not an athlon, more like a 486-586 cross.

This opcode problem affects certain distributions, such as Suse 8.2 and the first generation of Red Hat 9 CD-ROMs (download ISOs of red hat should be ok). You should avoid SuSe 8.2 and only use downloaded ISO images of Red Hat Linux. If you compile your own kernel notice that under processor type there are two C3 options. If you select the original C3, then the kernel will compile using -march=i486 option, which avoids the CMOV problem. See the gcc manual for more x86 options.

13.3. How do I install SuSe 8.2?

There are some problems running gcc generated i686 code on the C3 CPU. Most distributions are compiled for i386 or i586, so this isn't a problem, but there appear to be some issues with SuSe 8.2, whose 586 kernel sometimes won't run on the C3 processor. If you have problems with SuSe 8.2, then this procedure might work:

1) put your via harddisk in a supported computer
2) install SuSE on this computer / harddisk combination
3) go to /usr/src/linux and make make cloneconfig
4) make (x)config and change the cpu flag from pentium to 486
5) make dep, make bzImage, make modules, make modules_install
6) Install the new kernel, sometimes you must run mr_initrd
7) make a "test boot" if it works fine change the harddisk

13.4. EPIA Links

Here are some useful links which have been submitted to the HowTo:

• EPIA 5000 & M10K Answers @ Stargate

• Courville.org wiki

• Linitx.org

• Linitx.com

• Epiacenter.com

• mini-itx.com

13.5. The M10k is too noisy. How can I make it quieter?

The EPIA M10000 board uses a Nehemiah 1GHz CPU. The CPU features a small heatsink and a 40mm fan (in my case a BiSonic 4010 fan). Many M10k owners believe that the BiSonic fan is too noisy. There are several ways to reduce the noise from this fan. Which technique you should use depends on your sensitivity to noise, your budget and your abilities. I will start with the easiest methods and progress to the most difficult. Note that some of these methods may be combined.

13.6. DRI Only Works as root

This is a complicated problem because there are at least three different configuration errors that result in this behaviour.

1. Missing DRI section in /etc/X11/XF86Config. There must be a DRI section in the XF86Config file:

   Section "DRI"
       Mode 0666
   EndSection

   If you change the DRI section then you should remove the /dev/dri/card0 device file before restarting X

2. Incorrect permissions on /dev/agpgart. Change the permission on this file to 666, e.g.:

   bash# chmod 666 /dev/agpgart

3. Incorrect permissions on /usr/X11R6/lib/modules/dri/via_dri.so. Change the permissions on this file to 666, e.g.:

   bash# chmod 666 /usr/X11R6/lib/modules/dri/via_dri.so

4. Not enough video RAM. Go to the BIOS setup menus and make sure that at least 32MB is reserved for video RAM.

5. You must insert the agpgart module before via_v4l_drv. Edit /etc/modules.conf or /etc/modprobe.conf and reboot.

6. From Thomas Hellstrom:

   If the X server crashes for some reason it may fail to give back reserved AGP memory to the system. After some crashes the AGP memory space may be exhausted. Best way to remedy is to reboot.

13.7. DRI or GLX Crashing

The via_agp module must be installed before the via_v4l_drv module.

13.8. DMA Lockup Problem

Before talking about the VIA 686a DMA lockup problem, you should know that some distros, including fedora core (3?) ship a broken longhaul driver which will lock up your system under some circumstances. So before looking into the DMA lockup problem you should disable longhaul and retest your system.

The 8231 and 8235 southbridge chip tends to lock up when too much DMA activity is going on. Many people report lockups when trying to record video using the Haupage card. I have experienced the lock up when concurrently ripping a CD and copying large amounts of data between hard drives. This is a serious issue, as described in this viaarena thread.

VIA staff offer BIOS patches to address this issue. These patches are consider beta software (as of 16 June 2005) and are only offered for certain boards. Here are some links to patches for EPIA M, EPIA MII, EPIA CL. All reports suggest that the EPIA M patch works. Some people report continuing lock ups with the MII and CL patches. Here is some background information about the problem: