Agro,

first of all, thank you for your help.
I believe sound is enabled by bios (I use it in Win without big problems).
I tried to set all channels to max volume and unmute with alsamixer. No gain.
xmms works, shows vu-meter bars (leds) moving, but no sound heard.

My bootup strange lines, not using alsa (boot without any command):
...
APM bios found, power management functions enabled
apmd[61]: main(): apm_open() failed: No such device
...
Soundcard: Intel Corp.|82801EB AC'97 Audio controller driver=unknown
modprobe: modprobe: Can't locate module snd-slot-0
modprobe: modprobe: Can't locate module snd-service-0-0
Video is ATI|unknown device 1002:4164, using XFree86(vesa) Server
Monitor is ...
...

My bootup strange lines (using your suggestion, F2 knoppix alsa):

...
APM bios found, power management functions enabled
apmd[61]: main(): apm_open() failed: No such device
...
Video is ATI|unknown device 1002:4164, using XFree86(vesa) Server
Sound card: driver=ALSA(autodetect)
Preparing modules for alsa...
Building card database..
Configuring Intel 8x0..
Running update-modules...
Creating snddevices...
Setting default volumes...
...

Seems to me that my mainboard (P4C800 Deluxe) is not completely supported (APM?). Just a feeling...

This is a capture of /sbin/lsmod:

knoppix@ttyp0[knoppix]$ /sbin/lsmod
Module Size Used by Not tainted
snd-pcm-oss 35588 0 (autoclean)
autofs4 8724 1 (autoclean)
nls_iso8859-1 2876 0 (autoclean)
nls_cp437 4380 0 (autoclean)
snd-mixer-oss 11160 0 (autoclean) [snd-pcm-oss]
snd-intel8x0 16644 0 (autoclean)
snd-pcm 53888 0 (autoclean) [snd-pcm-oss snd-intel8x0]
snd-timer 13352 0 (autoclean) [snd-pcm]
snd-ac97-codec 31776 0 (autoclean) [snd-intel8x0]
snd-page-alloc 4320 0 (autoclean) [snd-intel8x0 snd-pcm]
snd-mpu401-uart 2960 0 (autoclean) [snd-intel8x0]
snd-rawmidi 12256 0 (autoclean) [snd-mpu401-uart]
snd-seq-device 3748 0 (autoclean) [snd-rawmidi]
snd 25828 0 (autoclean) [snd-pcm-oss snd-mixer-oss snd-intel8x0 snd-pcm snd-timer snd-ac97-codec snd-mpu401-uart snd-rawmidi snd-seq-device]
soundcore 3364 4 (autoclean) [snd]
i810_rng 2628 0 (unused)
serial 51844 0 (autoclean)
usbnet 12482 0 (unused)
usb-uhci 21868 0 (unused)
usbcore 57376 1 [usbnet usb-uhci]
apm 9768 0
rtc 6908 0 (autoclean)
cloop 7940 2

Any new suggestion?

PS: Video problem is the line:
Video is ATI|unknown device 1002:4164, using XFree86(vesa) Server
I don't know if it is a real problem (KDE is functional) but just to understand that "unknown"...

TIA.

zyx