The Dell XPS L401x L501x L701x series is a refresh of the XPS line and comes with an Nvidia Optimus configuration.
A DSDT.dsl table from a Dell XPS L501x model was submitted here:
http://bugs.launchpad.net/bugs/312756
See the link below for a review:
Support for NVIDIA Optimus models in Linux is still far from perfect, although more and more laptop models come with this configuration.
There are now more than 300 Linux users who joined the hybrid-graphics-linux Launchpad Team, and new developments are being incorporated
to the mainline Linux kernel to improve support of this graphics configurations.
Here are two new models that have been recently announced:
Equipped with a 2.4GHz Core i5-520M, 4GB of DDR3 RAM, a 320GB HDD and NVIDIA's GT 425M (1GB).
Acer Aspire 5742G with NVIDIA GeForce GT 540M
[Phoronix] Intel, NVIDIA Hybrid GPU Switching On Linux Nears
A month after making some small progress towards "hybrid graphics switching" on Linux to allow notebooks with dual GPUs (usually a low-power integrated graphics processor and a performance-oriented but high-powered discrete GPU), Red Hat's David Airlie is beginning to get things working for Intel and NVIDIA GPU combos on notebooks such as the Lenovo ThinkPad T410. Hybrid graphics on Linux still sucks, but at least it's getting better.
In a branch dubbed "drm-nvidia-switch" of David Airlie's Linux kernel DRM testing tree he has the kernel portion working for switching between the Intel IGP and the NVIDIA GPU with the open-source i915 and Nouveau DRM/KMS drivers, respectively. However, some bits are still missing and this will not work in all notebooks, but testing is just being done on the ThinkPad.
More details on this Linux GPU switching achievement can be found on David Airlie's blog.
