Well, finally I have all my hardware working with Gentoo, I have an Intel Core 2 Duo, with GeForce 7300 from Nvidia and an Intel ICH8 audio card, which is integrated in my mother board.

You may see the output of the hwinfo command in my PC here

And the output of lspci below

00:00.0 Host bridge: Intel Corporation 82P965/G965 Memory Controller Hub (rev 02)
00:01.0 PCI bridge: Intel Corporation 82P965/G965 PCI Express Root Port (rev 02)
00:03.0 Communication controller: Intel Corporation 82P965/G965 HECI Controller (rev 02)
00:19.0 Ethernet controller: Intel Corporation 82566DC Gigabit Network Connection (rev 02)
00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Contoller #4 (rev 02)
00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 02)
00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 02)
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02)
00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 02)
00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 02)
00:1c.2 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 3 (rev 02)
00:1c.3 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 4 (rev 02)
00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 5 (rev 02)
00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 02)
00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 02)
00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 02)
00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev f2)
00:1f.0 ISA bridge: Intel Corporation 82801HB/HR (ICH8/R) LPC Interface Controller (rev 02)
00:1f.2 SATA controller: Intel Corporation 82801HB (ICH8) 4 port SATA AHCI Controller (rev 02)
00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 02)
01:00.0 VGA compatible controller: nVidia Corporation G72 [GeForce 7300 SE] (rev a1)
03:00.0 IDE interface: Marvell Technology Group Ltd. 88SE6101 single-port PATA133 interface (rev b1)
07:03.0 FireWire (IEEE 1394): Texas Instruments TSB43AB22/A IEEE-1394a-2000 Controller (PHY/Link)

Read how to gentoo, nvidia, X and fluxbox to know how to make Nvidia and X work.

And for the sound, here are the steps I followed to make it work.

First compile the kernel, I am using

Linux gentoo 2.6.25-gentoo-r8 #7 SMP Sun Nov 16 16:29:29 BOT 2008 i686 Intel(R) Core(TM)2 Duo CPU E6550 @ 2.33GHz GenuineIntel GNU/Linux

That is the output of uname -a

And my Kernel configuration file is here

Check that the sound section is:

#
# Sound
#
CONFIG_SOUND=y

#
# Advanced Linux Sound Architecture
#
# CONFIG_SND is not set

#
# Open Sound System
#
# CONFIG_SOUND_PRIME is not set
CONFIG_HID_SUPPORT=y
CONFIG_HID=y
# CONFIG_HID_DEBUG is not set
# CONFIG_HIDRAW is not set

And the I2C hardware bus support is:

#
# I2C Hardware Bus support
#
# CONFIG_I2C_ALI1535 is not set
# CONFIG_I2C_ALI1563 is not set
# CONFIG_I2C_ALI15X3 is not set
# CONFIG_I2C_AMD756 is not set
# CONFIG_I2C_AMD8111 is not set
CONFIG_I2C_I801=m
# CONFIG_I2C_I810 is not set
# CONFIG_I2C_PIIX4 is not set
# CONFIG_I2C_NFORCE2 is not set
# CONFIG_I2C_OCORES is not set
# CONFIG_I2C_PARPORT_LIGHT is not set
# CONFIG_I2C_PROSAVAGE is not set
# CONFIG_I2C_SAVAGE4 is not set
# CONFIG_I2C_SIMTEC is not set
# CONFIG_SCx200_ACB is not set
# CONFIG_I2C_SIS5595 is not set
# CONFIG_I2C_SIS630 is not set
# CONFIG_I2C_SIS96X is not set
# CONFIG_I2C_TAOS_EVM is not set
# CONFIG_I2C_STUB is not set
# CONFIG_I2C_TINY_USB is not set
# CONFIG_I2C_VIA is not set
# CONFIG_I2C_VIAPRO is not set
# CONFIG_I2C_VOODOO3 is not set

Now that you have your kernel configured, according to your own needs, lets install the alsa drivers.

echo "media-sound/alsa-driver" >> /etc/portage/package.keywords

To unmask Alsa Drivers.

echo "media-sound/alsa-headers">>/etc/portage/package.keywords

To unmask Alsa Drivers dependencies.

emerge alsa-driver alsa-utils

To install the drivers and alsa-utils package.

Well, now configure your card.

alsaconf

and follow the instructions there.

Lets start alsasound daemon.

/etc/init.d/alsasound start

And make it start every time you boot your Linux.

rc-update add alsasound boot

Add yourself to the sound gruop

gpasswd -a audio replace username with your username, and some other you may want to add to that group, and have access to sound. To set the volume run:

alsaconfig

Be sure to unmute the master, the front and PCM channels That should be all, now you should have video and sound working with Gentoo.