Except that anything recent enough to have issues will work just fine on Windows 7 x64 even if its only 32-bit. With the exception of hardware drivers and a couple other wierd things, I have yet to see anything 32-bit that wont run on 64-bit systems. Every 32-bit game I have tried runs just fine on my 64-bit system (better than when I was running Windows XP in 32 bit on the same CPU even)