In the last two days, i have spent my time debugging and hacking my ASUS UL80VT laptop in order to work with asus-switcheroo project by A. William. It's another attempt to enable GPU switching, but it's designed specifically for ASUS laptop, while previous attempt by Dave Airlie was supposed to work on any hybrid laptop (apparently, it wasn't the case in mine). There's no Slackware's way, so i have to see the Makefile and adjust it with Slackware's way to get it done . I hope i can contribute to the project by adding Slackware's HowTo on the Makefile someday
So far, i have been able to enable /sys/kernel/debug/vgaswitcheroo/switch so that i can switch between Intel/NVidia card, but the problem is that it still uses nouveau driver, which as you already know doesn't provide any 3D acceleration for NVidia card. That's why i'm still working with A. William to make it work with my NVidia card. There's one step left for this to work, so it should be finished by the end of this week hopefully
Even though some people reported it's working on 2.6.37.x kernels, i believe the best option for asus-switcheroo project to work is by upgrading to Linux Kernel 2.6.38.x series. This is based on my experience where i have just upgraded to kernel to 220.127.116.11 and suddenly, the previously non-working module now works as intended.
I will write the detailed steps after i have completely able to work with my NVidia card with proprietary driver. Wish me luck