Re: Do I need 64Bit if RAM is more than 4 GB?

[Paul Brook <paul@codesourcery.com>]

On Wednesday 08 September 2004 14:45, Ron Johnson wrote:
> In fact, it seems to me that *any* 32 bit processor (SPARC, HPPA,
> Power) that wants to be able to use more than 4GB of total RAM
> would have to use such a segmentation scheme.

Err, all of the above have 64-bit variants. I don't know if the 32-bit 
variants support more than 4GB ram, but I doubt it.

The 64-bit Power CPUs don't have a real 32-bit mode. They always operate on 
64-bit registers. 32-bit code is executed by automatically sign- or 
zero-extending 32-bit memory loads, and certain instructions (eg. 
comparisons) ignore the top 32 bits.

I suspect SPARC does something similar, I don't know about PARISC.

Paul