Having been an Adobe Lightroom user for many years and becoming frustrated with the lethargy of Win 7, 32bit and also not being able to upgrade to the latest version of Lightroom which only runs on 64bit OS, I bit the bullet and took advantage of the free upgrade path to Win 10, 32bit and then did a clean install of Win10 64bit.
I followed the readily available guidelines carefully and decided to install the new 64bit image on a clean SSD drive so I could keep my old SSD should there be any serious dramas. All seemed to go to plan until I had to restart the PC when re-installing Lightroom, after which I encountered the black screen of death!
I will cut the long story short by saying that after many re-starts and attempts to repair the installation I noticed, following one of these re-starts that the mouse pointer was present on the black screen. A quick Google on my tablet alerted me to the possibility of a graphics driver issue. Indeed the mouse pointer seemed to be able to go well beyond the edges of the monitor.
The solution involved pushing the set-up button on the monitor following which I discovered that the "real" windows desktop existed as a pip in a corner of a large black area. By enlarging the pip I could work with is as normal and was able to update the graphics driver and then set the monitor to its normal mode of operation.
Since then Win 10 64bit has been fine and with 16gig of RAM on board I am very happy! But what a lot of messing around and tearing hair out! Be warned!
Best of luck
ps, I had never used a pip on this PC previously.