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Re: powerpc

On Tue, Aug 17, 1999 at 03:37:19AM -0500, Luis Garcia Alanis wrote:
> On x86 tech the CPU has only like very, very few registers, and     so it 
> really needs the next instructions FAST, so a change on the system bus 
> makes a lot of a difference, but on RISC, that has lots of registers, 
> that might not be the case, isn't it? 

I don't think that has a lot to do with it, the register are only for data, and
the more register would accelerate the demand for new instructions. But ppc
instructions are 32bit long, and all current ppc processor, with their 64bit
memory access can retire 2 instructions per cycle. compared to intel's variable
length instructions, this could make the bus speed less important ?

Also consider the size of the L1 cache ? the G3 has a 32kb instruction L1 cache
and another 32kb data cache, that is more than what intel processors have.



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