1) What are the limitations of Windows XP / Vista regarding multi-cores / CPUs support ?
We have to consider two alternatives :
* Windows XP Home, Vista Starter and Home Basic / Premium: can use only one CPU, but is not core-limited. Good for a single CPU quad core.
* Windows XP Pro, Vista Business, Enterprise, Ultimate: can use a maximum of two CPUs, not core-limited. Good for a dual CPU quad core (e.g. dual Xeon workstation).
1 CPU, single core:
All systems
(e.g. Athlon 64)
1 CPU, dual core:
All systems
(A64 x2, Core 2 Duo)
2 CPU, dual core:
Windows XP Pro or Vista >= Business
2 CPU, single core:
XP Pro or Vista >= Business
2) Why are 64 bit CPUs a very good thing for 3D ?
* They are faster (more registers, ability to manipulate very large numbers in one operation).
* They can adress more memory.
BUT : to benefit from 64 bit computing, you need two other things :
* A 64 bit operating system like Windows XP 64 or Windows Vista 64 bit
* A 64 bit version of your software. Among the 3D applications discussed here, Cinema 4D and Vue 6 Infinite are available in 32 bit and 64 bit versions. The speed increase typically varies between 5 and 15% compared to the 32 bit versions.
However, the real deal is the possibility to address more memory. Under Windows XP / Vista 32 bit, each application can only use a maximum of 2 GB (2 GB are reserved for the kernel). And even if you install 4 GB on your PC, you won't see more than 2.75 or 3.00 GB in Windows (the rest is used by the hardware and unavailable for the applications). Under Windows XP / Vista 64 bit, each application has access to all the memory. The address space is 128 GB: this is much more than what most motherboards support today.
With 64 bit applications, we can render faster, but the most important thing is: we can build more complex scenes, with higher-resolution textures and more complex geometry. You will be limited by the amount of RAM installed in your PC, but not by the application itself. (see the'64-bit is useful !' animation in the Animations section)
