Dual Athlon MP 1U units

[Joel Jaeggli]

On Sat, 26 Jan 2002, Ben Ransom wrote:

> Are PFC (power factor correction) power supplies standard,

One would assume that by power factor correction that they mean reducing 
the difference between working power and apparent power... In general 
switching power-supplies re fairly efficient anyway, so one would have to 
evaluate their claims based on the design of the power supply. The crucial 
thing to bear in mind with smp athlons is can the power-supply provide the 
current rise need when the cpu's switch from idle to going full-bore.

> or something 
> special wrt providing only required power and therefore less heat?

switching power supplies only provided required power awayway. if you plug 
a dual athlon mainboard based system with a 560watt power supply into ac 
power it should draw something like 1.7 amps... if you plug in a 300watt 
power supply instead it should still draw 1.7 amps.

>  A 
> vendor told me that a dual 1900 Athlon on Tyan 2466 mboard can be run in 1U 
> if done with a 300w PFC power supply.  Do they know some great secret, or 
> are they stretching physics?

probably their power supply has an extra set of caps on the 3.3 and 5 
volt rails to cope with the rise in current demand.

> PS:  AMD shows one vendor's case approved with the Athlon MP running at all 
> available clock speeds, i.e. that would include 1900+
> -Ben Ransom
> 
> 
> At 02:30 AM 1/26/2002 -0600, you wrote:
> >Velocet wrote:
> > >
> > > Whats the power dissipation of running dual 1.2 GHz Mp's? How about for
> > > 1.33Ghz regular athlons in non-SMP configs as comparison? (As well, how 
> > much
> > > heat comes off typical power supplies to run these systems?)
> 
> _______________________________________________
> Beowulf mailing list, Beowulf at beowulf.org
> To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
> 

-- 
-------------------------------------------------------------------------- 
Joel Jaeggli	      Academic User Services   joelja at darkwing.uoregon.edu    
--    PGP Key Fingerprint: 1DE9 8FCA 51FB 4195 B42A 9C32 A30D 121E      --
The accumulation of all powers, legislative, executive, and judiciary, in 
the same hands, whether of one, a few, or many, and whether hereditary, 
selfappointed, or elective, may justly be pronounced the very definition of
tyranny. - James Madison, Federalist Papers 47 -  Feb 1, 1788