[Beowulf] Power calculations , double precision, ECC and power of APU's

Vincent Diepeveen diep at xs4all.nl
Fri Mar 22 13:09:15 PDT 2013


On Mar 22, 2013, at 3:55 PM, Geoffrey Jacobs wrote:

> On 03/22/2013 09:42 AM, Vincent Diepeveen wrote:
>>
>> Suddenly only single precision without ECC is interesting. First time
>> in history i've see anyone on this list care for that.
>> Past decades only double precision with ECC mattered. Single
>> precision overclocked and missing bits as always as all those
>> gpu's do because of total overheating, was only for the gamer kids
>> who fry every few months a videocard so to speak,
>> because of too high of an overclock.
>>
>> Now intel releases a built in gpu line which obviously has no ECC
>> inside the gpu and i doubt it has any double precision
>> significance, and then suddenly only single precision without ECC is
>> interesting.
> No ECC might be an issue. Public information states approximately 2 SP
> ops per DP op. Sounds like the SIMD registers can do both, like a  
> normal
> x86 chip.

For graphics registers of a built in GPU at a cpu they're gonna sell  
to kids gaming?

I would be very amazed if it can do double precision at all.

AMD and Nvidia do or intend to do that  for the cheapest gamers cards  
as well.
It just can hardly do double precision. The 2 for 1 ratio is a  
theoretic number that practical needs to be
tested and only the highend versions might have enabled those  
transistors.

Adding ECC to a GPU is a major problem and really not something that  
you 'just add'.
It has huge bandwidth implications, especially limitations, i  
understood from a knowledeable hardware engineer
whose name shall not be quoted and who for sure doesn't speak for any  
known manufacturer
and sure not when talking to me.

> I'm not the biggest Intel fan, but untruths and deception don't add to
> the dialog on this list.
>

If you want to run double precision matrix calculations, just test  
that at it and get horrified...

>> A dutch saying is: "whose bread you eat his word you speak"
>>
>> That's the only relevant saying here and nothing else.
>>
>> On Mar 21, 2013, at 5:45 PM, Lux, Jim (337C) wrote:
>>
>>> The beard must have grey in it.
>>>
>>> Jim Lux
> <snip>



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