ho eseguito la modifica e il file modules è il seguente anche se riavviando il pc mi vede la scheda come una Realtek ALC655 :

# /etc/modules: kernel modules to load at boot time.
#
# This file should contain the names of kernel modules that are
# to be loaded at boot time, one per line. Comments begin with
# a '#', and everything on the line after them are ignored.
ide_scsi
tmscsim
usbcore
uhci_hcd
ohci_hcd
usb_storage
ub
ieee1394
ohci1394
sbp2
rtc
ac
battery
button
fan
processor
thermal
pcmcia_core
yenta_socket
ds
serial_core
8250
parport
parport_pc
agpgart
via_agp
crc32
mii
8139too
ac97_codec
soundcore
snd
snd-via82xx
uart401
via82cxxx_audio
nls_cp437
nls_iso8859_1
af_packet
autofs4
ali_agp
amd64_agp
amd_k7_agp
ati_agp
efficeon_agp
intel_agp
intel_mch_agp
nvidia_agp
sis_agp
sworks_agp
jbd
ext3

attendo consigli grazie