Re: Good PSU choice? CORSAIR CMPSU-650TX 650W ATX12V / EPS12V SLIReadyCrossFire Ready 80 PLUS Certif

K

krw

The 80-Plus rating is a type of guarantee of 80%+ efficiency at several
load levels, from 20% on upto 100%. There will be a level at which any
power supply will be most efficient somewhere between that (perhaps
it'll be 90% efficient at that level), but it should remain at or above
80% efficiency all throughout its range.
Click to expand...

Psst, sailor! Wanna buy a bridge in Brooklyn and perhaps some flat-lands in
Florida.
 
R

Robert Redelmeier

In comp.sys.ibm.pc.hardware.chips willbill said:
It is also a 80+ gold PSU, which means that at 10% usage
to 20% usage, which is where you'll be most of the time,
it is 82-to-88% efficient.

Also see:
http://en.wikipedia.org/wiki/Power_supply_unit_(computer)
and > > http://en.wikipedia.org/wiki/80_PLUS
Click to expand...

I do not see any references to 80+ efficiency below 20% load,
and in fact a specific disclaimer that efficiency may be well
below 80% at loads below 20%, the min the 80 PLUS spec rates.

Of all the specs, I expect 80% efficiency at 20% load to
be the hardest to reach with a sharp dropoff.

-- Robert
 
W

willbill

I do not see any references to 80+ efficiency below 20% load,
and in fact a specific disclaimer that efficiency may be well
below 80% at loads below 20%, the min the 80 PLUS spec rates.

Of all the specs, I expect 80% efficiency at 20% load to
be the hardest to reach with a sharp dropoff.
Click to expand...

The efficiency at 10% load was in the Anandtech review
of the Corsair AX750 80 Plus Gold unit. See:
http://www.anandtech.com/show/4011/corsair-ax750-80plus-gold

If anything, I think that another instructive thing that one
can/should do is to go to www.newegg.com and pull up
only the power supplies that newegg offers from say Corsair
(and Antec is another) and list it on a single page, sorted
by lowest price 1st; Both Corsair and Antec compete
at the low end and those cheap units are clearly not
as good as their high end units (80+ gold/platinum).

Bill
 
R

Robert Redelmeier

In comp.sys.ibm.pc.hardware.chips willbill said:
The efficiency at 10% load was in the Anandtech review
of the Corsair AX750 80 Plus Gold unit. See:
http://www.anandtech.com/show/4011/corsair-ax750-80plus-gold
Click to expand...

Yes, it is there. 82% at 10% load. Very nice (only
slightly marred by the Corsair ad on the same page).
by lowest price 1st; Both Corsair and Antec compete
at the low end and those cheap units are clearly not
as good as their high end units (80+ gold/platinum).
Click to expand...

This is reasonably certain. What is far less certain is whether
the additional price (up to 10x) is worth paying, and for whom it
might be. $100 is not a trivial investment for all users. Those
with noisy power would probably be better to put it into a UPS.
Surges are best handled by first making sure your house ground is
solid, then by a whole-house MOV installed in the breaker panel.

I see a lot of competition in the PSU arena, with 80 PLUS and PFC
trying to establish a premium in a very skeptical market. I can see
why -- PFC started with TuV (German) 10+ years ago, but I've never
heard electric providers complain (as they do for industrial users).

The importance of Efficiency is more a matter of usage
patterns. Leaving a hipowered x86 system running, even idle
at ~100W seems a loser. Better to boot the box when it is
going to be used, then shutdown. Better also for MS OSes
which need periodic reboots. And MS has been improving boot
times which builders can improve further with SSDs.

If you need instant availability, consider a second low
power system (I use nettops) plugged into reasonable
kbds, mice & monitors. Through KVM if needed. 20W


-- Robert
 
K

krw

Yes, it is there. 82% at 10% load. Very nice (only
slightly marred by the Corsair ad on the same page).


This is reasonably certain. What is far less certain is whether
the additional price (up to 10x) is worth paying, and for whom it
might be. $100 is not a trivial investment for all users. Those
with noisy power would probably be better to put it into a UPS.
Surges are best handled by first making sure your house ground is
solid, then by a whole-house MOV installed in the breaker panel.

I see a lot of competition in the PSU arena, with 80 PLUS and PFC
trying to establish a premium in a very skeptical market. I can see
why -- PFC started with TuV (German) 10+ years ago, but I've never
heard electric providers complain (as they do for industrial users).

The importance of Efficiency is more a matter of usage
patterns. Leaving a hipowered x86 system running, even idle
at ~100W seems a loser. Better to boot the box when it is
going to be used, then shutdown. Better also for MS OSes
which need periodic reboots. And MS has been improving boot
times which builders can improve further with SSDs.

If you need instant availability, consider a second low
power system (I use nettops) plugged into reasonable
kbds, mice & monitors. Through KVM if needed. 20W
Click to expand...

I just use a (docked) laptop and Standby. I don't generally boot more often
than every couple of months (needs to shut down to undock).
 
W

willbill

...What is far less certain is whether
the additional price (up to 10x) is worth paying, and for whom it
might be. $100 is not a trivial investment for all users. Those
with noisy power would probably be better to put it into a UPS.
Surges are best handled by first making sure your house ground is
solid, then by a whole-house MOV installed in the breaker panel.

I see a lot of competition in the PSU arena, with 80 PLUS and PFC
trying to establish a premium in a very skeptical market. I can see
why -- PFC started with TuV (German) 10+ years ago, but I've never
heard electric providers complain (as they do for industrial users).

The importance of Efficiency is more a matter of usage
patterns. Leaving a hipowered x86 system running, even idle
at ~100W seems a loser. Better to boot the box when it is
going to be used, then shutdown. Better also for MS OSes
which need periodic reboots. And MS has been improving boot
times which builders can improve further with SSDs.

If you need instant availability, consider a second low
power system (I use nettops) plugged into reasonable
kbds, mice & monitors. Through KVM if needed. 20W

-- Robert
Click to expand...

Hey Robert, what I've seen suggests that expensive PC
PSU units *do* pay off over their 3/4 year power useage.

Whether their lower ripple is noticeable for high end PC
audio is the open issue for me. But I'm actively working at that.

Bill
 
R

Robert Redelmeier

Hey Robert, what I've seen suggests that expensive PC
PSU units *do* pay off over their 3/4 year power useage.
Click to expand...

Why "suggests"? This is trivial to calculate and know for
certain. From your "3 PSU" review sidethread, the bottom end
exploding PSU still managed 74% efficiency vs 82% for the top
end (both at 20% load). So you can expect the cheapo to use
11% (relative) more kWh for any given system load.

A mostly idle system but powered 24/7 averaging 100W uses US$96/yr
worth of electricity at $0.11/kWh . Savings = $10/yr . And this is
the high-side (for a home user). A more reasonable duty cycle would
be 40h/week, perhaps averaging 200W (peak higher). This only uses half
the electricity and the higher efficiency only brings half the savings.
The price difference in the article was 'way more than $20.

Now, some people might find the peace of mind or bragging rights
worth the premium. Or someone in a datacenter with higher loads might
actually find it pays, especially considering mtce & cooling.
Whether their lower ripple is noticeable for high end PC
audio is the open issue for me. But I'm actively working at that.
Click to expand...

Or golden ears. Check the frequencies of that ripple.
I'd expect around the freq of the switchers, 30-50 kHz.

-- Robert
 
D

daytripper

I've seen recommendations about so-called "whole-house surge
suppressors", but no one, to date, has actually been able to
demonstrate that such a thing is actually made and is available for
sale to the public.
Click to expand...

Good chance they thought you could find plenty of answers on your own ;-)

Googling "whole house surge suppressor" sure turns up a boat-load of on-target
items that are easily obtainable by any schmuck with the cash. Whether one
subscribes to the effectivity of same is likely a whole 'nuther discussion...

/daytripper
 
R

Robert Redelmeier

In comp.sys.ibm.pc.hardware.chips chrisv said:
I've seen recommendations about so-called "whole-house surge
suppressors", but no one, to date, has actually been able
to demonstrate that such a thing is actually made and is
available for sale to the public.
Click to expand...


I got mine at Home Depot. Hidden in one corner of the electrical
cage. Fits into the electrical breaker box on two adjacent soaces
(to catch both 110V phases) and tied to the ground bar. In some
places, local regs require installation by a licenced electrician.

-- Robert
 
D

daytripper

You're right, but I'd swear that it didn't, the last timie I tried,
which was maybe a few years ago... Oh well.
Click to expand...

Jeeze, your orbit has developed a seriously elongated period, Chris ;-)

Cheers
 
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