juanrga (nospam.delete@this.juanrga.com) on August 11, 2014 7:28 pm wrote:
> Michael S (already5chosen.delete@this.yahoo.com) on August 10, 2014 6:01 am wrote:
> > juanrga (nospam.delete@this.juanrga.com) on August 10, 2014 5:34 am wrote:
> > > Evidently the x86 tax is more noticeable on small phone-like cores but the tax doesn't magically
> > > vanish for big cores (only reduces the amount by a factor of about 2x or 3x). This is the reason
> > > why a 90W ARM SoC is able to offer 80--90% of the performance of a Haswell 140W Xeon.
> >
> > How it could be true when there exists neither 90W ARM SoC nor 140W Haswell Xeon?
> > http://ark.intel.com/products/codename/42174/Haswell#@Server
> >
>
> 90W ARM SoCs were presented recently

Do you know the difference between paper and silicon? Or between estimates based on preproduction silicon/preproduction boards and measurements on production systems?

> and there are several E5 Haswell Xeons rated at 140W.

E5 - unlikely. 130W - yes, but not 140W.
There exist one odd 150W IvyB Xeon-E5 part. Not sure for what reason, but most likely it's made for super-expensive workstations rather than for servers.

140W E7 is likely, but Haswell-based E7 is still half a year off.

>
> There are also several 135W and 145W Haswell Xeons.

Click on link. There are none.
Haswell-based Xeon-E5 is likely to be launched in the 2nd half of September. Right now it is not available for public benchmarking, only for internal one. So, there are no performance figures to be taken as 100% in order to derive what constitutes 80-90%.