Deleted my original comment. When I did, it deleted all replies to the comment. Sorry Pokester.
I thought I mentioned that here, I guess not, but kingfish did on this thread : Nvidia is dropping support for 32-bit operating systems. I think I must have mentioned it at Nvidia Forum.
Found this interesting statistics from AnandTech.com concerning Nvidia dropping 32 bit drivers and how many people still have 32 bit OS operating:
According to Steam hardware survey there are 2.19% of users who continue to use 32-bit Windows. Those 32-bit systems are legacy machines and PCs that have to run old programs or hardware natively. Owners of such computers are hardly interested in the latest GPUs (modern graphics cards may come with more memory than a 32-bit OS can address) or driver features, so the end of support will likely go unnoticed by the vast majority of involved parties. Meanwhile, 2% – 2.2% out of a billion of PCs in use worldwide is 20 – 22 million systems (the actual number will be higher because not all PCs run Steam). Therefore, there definitely will be disgruntled owners of 32-bit PCs running entry-level GPUs released in the recent years and now left without updated driver support for the latest GPUs.
Seems like AMD is going the same route. All of the RX series and VEGA Series GPU cards don't have 32 bit drivers.
Radeon™ RX 500 Series
Radeon™ RX 400 Series