64bit vs 32bit

You're limiting your thinking to only games. There are many business, technical and scientific software that need and use many cores, and more than 8GB of memory.

Because some people like me enjoy running all games with all the settings maxed out for a while before upgrades. It is also the same reason people would much rather drive a corvette or Lamborghini than a Prius. They will both get you the same place but one is a lot cooler than the other.

32-bit OS can't use more then 4GB of RAM, I use 5GB - 6GB when I'm gaming and 7GB - 8GB when I'm editing pictures, also 64-bit games wont work on 32-bit systems while 32-bit will work on 64-bit.

64bit is really great for servers, and just having 64bit vs 32bit is a very minor performance improvement, although small.

There are many, many advantages to using a 64 bit environment.

First, the 64 bit extensions (generally called x64, or long mode) for Intel and AMD microprocessor radically change the way that the microprocessor works. I won't go into great detail, but the x64 instruction set, ABI, and memory management is much cleaner and nicer than the i686 standard used back to the Pentium Pro, or even older i386 standard used back to the original Intel 386. Even if the microprocessor is put into compatibility mode to run a 32 bit game, it will still use x64 extensions throughout the operating system which leads to a much smoother and much more secure setup.

Second, the 64 bit extensions allow clean support for more than 4GiB of virtual memory. Contrary to popular belief, Intel microprocessors have supported more than 4GiB of physical memory since the Pentium Pro was introduced in 1995 (i686 mentioned above) and Microsoft Windows has supported more than 4GiB of physical memory since Windows 2000 Server. 32 bit Consumer versions of windows are restricted to 4GiB for marketing and compatibility reasons. However, in any 32 bit mode (also called protected mode) each application is still limited to a total 4GiB virtual address space, of which 2GiB is reserved for the system (shared among all running processes) and 2GiB is for the application. A compiler switch can shift this to 1GiB for the system and 3GiB for the application, but that can cause problems if the system actually needs more than 1GiB for itself. Games have been slamming into this barrier for years, and only recently have developers started dropping support for 32 bit versions of Windows. Several upcoming titles are 64 bit only, while several recent releases have crippled 32 bit support. Many gamers would have loved to see a 64 bit version of Skyrim because that game is notorious for needing more memory than it can get.

Third, Even if a game is the dominant running task on a system, it is never the only running task on a system. I like being able to game without having to first shut down my development virtual machines. I have enough memory and spare CPU time to have everything running at once.