I did the Windows 8 upgrade to my workhorse Vaio Z3 (short for Vaio, Z Series, 3rd Generation) today. My experiences from testing with the Asus Vivobook had been mostly positive, and as I had started getting bluescreens to Windows 7 in Vaio, it crashed if it went to sleep mode, the PMD discrete Radeon card was no longer recognised, etc., it would had been necessary to reinstall its OS in any case.
It was necessary to unplug the PMD during the installation, as that peripheral meant that Windows 8 would get stuck into the adding devices phase. And that meant borrowing another external DVD drive to access the installation media from, but otherwise the process was pretty straightforward. Some drivers had to be removed prior to installation and loads of drivers for Windows 8 were available from the Sony support page for Windows 8 upgrade. The only thing missing was the display driver for the hybrid Radeon/Intel display system Vaio Z3 is using. I try to post the link for that later, it is an unofficial beta thing, but seems to work fine with the PMD.
frans goes blog 
Here are some driver locations in case someone attemps similar Windows 8 upgrade of Vaio Z3:
– Official Windows 7 drivers (originals and updates) and the Windows update driver & utility files for this model (SVZ1311C5E): http://www.sony.fi/support/fi/product/SVZ1311C5E/updates
– Beta drivers for the PMD users (hybrid Intel / AMD display drivers – you need first install this beta package, which will then set up the installer for the official Catalyst driver, so the installation requires two phases. Also, you need to accept “unsigned” drivers, so proceed only if you are fine with that): http://leshcatlabs.net/index.php/2012/11/catalyst-12-11-beta4-unifl-for-amdintel-graphics/
For those interested in the UnifL driver, there is a manual here: http://leshcatlabs.net/manual/
Also, a new version of the driver package has already been released: http://leshcatlabs.net/index.php/2013/01/leshcats-catalyst-13-1-whql-unifl-for-amdintel-laptops/
To update: the 13.1 UnifL driver did not work in my Vaio Z3, had to boot to safe mode (hint: use shift-F8 to get boot menu in Win8), and then remove all display drivers and reinstall the 12.11 Beta4/Beta6 version (link above). The brightness issue was a tricky one: the brightness setting would go down to minimum regardless what. The solution came from the same place as the display driver: UnifL Brightness Resolver: http://leshcatlabs.net/index.php/2013/01/unifl-brightness-resolver-updated-till-v4-0/
The tool lets you manipulate some registry values. I am not sure I have got the issue completely fixed, but “FB60” was the value that has produced the best outcome so far.
Thanks for the information on UnifL driver. It has quickly evolved to 13.2 Beta 5, I wonder have you tried that yet?
Hi httimchen – thanks for the notice, no, I have not yet tested the 13.2 beta version. I might actually take it to ride, since the brightness problem came back and it is really irritating (the Vaio screen going dark all the time), maybe the 13.2 would fix it, as someone said in the comments of UnifL site.
Ok, I have now installed this one to my Vaio Z3:
http://leshcatlabs.net/index.php/2013/02/leshcats-catalyst-13-2-beta-5-unifl-public-testing/
-So far, it looks good: the brightness setting is indeed working now. But it is too early to say whether there will be some other, new issues in this beta. I am away from the office and thus cannot test how this behaves with the PMD atm.
great to hear that! look forward to knowing how it works on PMD! finger crossed 😀
I think I got the 13.2 Beta 5 finally working also with the PMD/AMD Radeon discrete card. This was not so straightforward, tough: there was a yellow exclamation mark next to the Radeon chip in the Device Manager and the external display was not detected. I needed to uninstall all display drivers (Intel & AMD), do the Driver Fusion cleaning (UnifL manual has the instructions), and then reinstall the Beta 5. Then all was working, but I think I made a mistake by trying to run the “remove watermark” tool, as it messed up the Windows 8, and had to reinstall everything once more. Keeping fingers crossed this works now, at least the brightness and docking/undocking from the PMD have been working in the few tests I have run so far.
Interesting and worthy driver development work, but shame this kind of techical stuff takes so much time to sort out.
I will try jumping through hoops in next couple days. It’s kind of sad that the community has to do this kind of work for SONY.
Nevertheless, Z3 is just too good to let go. It has the best computational power / weight ratio 😀
Unfortunately in my case the Beta 5 driver installation has now started falling apart: pressing the PMD eject button does no longer create any result, the brightness setting is no longer holding. Hopefully there will be a new version soon!
in case you miss it, Sony has finally released the new AMD driver
http://esupport.sony.com/US/p/swu-download.pl?mdl=SVZ131190X&upd_id=8740&os_group_id=24