Re: amd64 running on Intel Celeron and Pentium?

On 4/17/22 4:52 AM, Cyril Brulebois wrote:
> Elmar Stellnberger <[email protected]> (2022-04-17):
>> I haven´t heard yet of a Pentium IV supporting amd64.
>> Likely it does not exist.
> 
> https://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_processors seems
> to disagree in general. Willamette seems to be old enough to be 32-bit
> only though.
> 

Interesting. The architecture is called amd64 quite rightfully in my 
opinion, as it was first introduced by release in 2003 of Opteron CPU 
(project Hammer) by AMD (Advanced Micro Devices):

https://en.wikipedia.org/wiki/Opteron

However, Intel continued calling CPUs "Pentium 4" and since 2004 Intel 
CPUs in Wikipedia article Cyril mentions:

https://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_processors

are said to be "Intel 64". That article does not mention the core CPU 
data width not address width. If my memory serves me, these were the 
same 32 bit CPUs with "physical address extension" just expanding the 
ability of CPU to handle larger address space. So, wikipedia article 
about Pentium CPU is at least wrong when it points "Intel 64" to Opteron 
(Amd64 or its x86_64 synonym). But somebody more knowledgeable in the 
history may correct me.

<rant>
Incidentally, technical documentation on Intel website for these later 
pentiums is not acessible. I just tried to take a look at the technical 
documentation to prove for myself that I'm wrong above... but no 
information from primary source: Intel, just something on wikipedia (and 
we don't even know who takes responsibility for what wikipedia page says).
</rant>

Valeri

PS Of course, 32 bit CPU core can handle 64 bit data and addresses by 
using multiple operations for what 64 bit CPU will use a single one. 
Like pocket calculators which are using 1 to 4 bit addition register, 
yet happily processing really large numbers.

> 
> Cheers,