Graphics card:  Nvidia GTX 460 (supported by noveau driver, codename NVC0 / Fermi)

Trying nouveau driver, problems that no KMS is enabled:
[ 29.825] (EE) [drm] KMS not enabled
[ 29.826] (EE) No devices detected.

Displaying cat /var/log/kern.log |grep fb0: shows that there is no FrameBuffer assigned. It should show:
fb0: nouveaufb frame buffer device.

Reading:
http://nouveau.freedesktop.org/wiki/KernelModeSetting/
http://unix.stackexchange.com/questions/83319/how-can-i-know-if-the-current-kernel-was-compiled-with-a-certain-option-enabled

KMS could not be enabled, FB:0 is still not set … tried to install noveau.ko through insmod but it was hard (because you have to install dependencies manually)
dmesg | tail (shows errors from insmod)
uname -r
cd /lib/modules/3.13.0-43-generic/kernel/drivers

$ sudo insmod ./platform/x86/wmi.ko
$ sudo insmod ./platform/x86/mxm-wmi.ko
$ sudo insmod ./gpu/drm/nouveau/nouveau.ko
$ sudo insmod ./i2c/algos/i2c-algo-bit.ko
$ sudo insmod ./acpi/video.ko
$ sudo insmod ./gpu/drm/nouveau/nouveau.ko

nouveau module was loaded, I had to load it manually and also dependencies:

drm
drm_kms_helper
ttm
wmi
mxm_wmi
i2c-algo-bit
video
nouveau

through sudo modprobe <name>
or
sudo insmod /lib/modules/$(uname -r)/kernel/drivers/platform/x86/wmi.ko

path:
/lib/modules/$(uname -r)/kernel/drivers/platform/x86/wmi.ko
/lib/modules/$(uname -r)/kernel/drivers/platform/x86/mxm-wmi.ko
/lib/modules/$(uname -r)/kernel/drivers/platform/x86/wmi.ko
/lib/modules/$(uname -r)/kernel/drivers/platform/x86/wmi.ko
/lib/modules/$(uname -r)/kernel/drivers/gpu/drm/nouveau/nouveau.ko

How to load them permanently:
1) add them to /etc/modules (only names nothing more)
2) sudo update-initramfs -u
The update-initramfs script manages your initramfs images on your local box.

But still nouveau was loaded manually, framebuffer was  assigned, but after reboot all modules except nouveau were loaded.

After more googling found that it was maybe blacklisted. And really, search in the /etc/modprobe.d/ found that file nvidia-current_hybrid.conf contained:
# This file was installed by nvidia-current
# Do not edit this file manually
blacklist nouveau
blacklist lbm-nouveau
alias nouveau off
alias lbm-nouveau off

Started working
After commenting these out nouveau started to work after reboot. Problems:
* Can’t wake up from sleep. Display shows, but freezes, can’t even change to console.

Desktop performance: great. But sometimes flash of older screen (screensaver for example) flashes in Chrome.
Games:
Neverball (3d): all good.
Fez: fine, better and smoother than on radeon.
Quake 3: good as usual.
Spy chameleon RGB agent: all good.
Gratitious space battles: all good
Nexuiz: all good
Etherlords through wine 1.6: missing textures. very choppy.

Big problem: after sleep / wakeup any 3D application stops working / or hangs pc.

Interesting reading:
Benchmarks of Windows 8 Pro, Ubuntu 13.10 with Nouveau, and Ubuntu 13.10 with proprietary NVIDIA driver; with GeForce 9800GTX, GTX 460, GTX 680.
http://www.phoronix.com/scan.php?page=article&item=nvidia_windows8_geforce&num=7