Hi all!
I recently got a second hand x505zp, and after using it in xp for a day, decided to try windows 7. I had read about it beforehand, and gathered a few helpful guides.
The most interesting part is perhaps that I did the install over network from my vista desktop pc. I did so using a combination of these guides:
http://blog.ryantadams.com/2008/02/01/how-to-boot-from-the-network-pxe-boot-with-tftp-and-windows-pe/
http://rickatnight11.com/?p=181
... using an already vLite-treated Windows 7 RC version. There were a few small changes needed in the tftp/pxe boot (I can only remember not using \\ in front of username during mapping of cd (I actually used a mounted image))
After install of the original utilities and telling windows where to find the right drivers (I had downloaded them from ftp://ftp.vaio-link.com/pub/Vaio/ORIGINAL/), everything seems to work.
I have not been able to rate the performance using windows, but in combination with Chrome it is pretty damn fast (even though it uses 271 mb ram at rest). Will come back with some more after I have had time to use it.
EDIT: I had some serious trouble with the display adapter, but now I think it finally works. Windows would reinstall generic (VgaSave) drivers everytime i rebooted, causing sleep to be unavailable (though not much else, just very annoying). The solution seems to be to completly uninstall all display drivers and delete them from the HD (option when you choose to uninstall), don’t reboot when prompted, install preferred drivers (I used DriverMax and this driver: http://justendeal.com/driver/855gm_vista_driver.zip). Just to be safe I pulled out the WLAN card before rebooting (to avoid windows update), and it has worked since.