Power Supply only lasts 6-9 mths - any ideas?

  • Thread starter Thread starter Ian Roberts
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Ian Roberts

Hi

I'm now on my 3rd power supply.

I bought a £75 550w p/s from a well know high street component supplier.

Everything worked fine for ages but I then found every so often when I
pressed the on button the lights would come on for a second as if its about
to startup and then nothing - dead as a dodo.

The only way I could get it to start was to disconnect from the mains for a
few seconds, plug it back in and then try again. It would work OK for the
next few start ups and then the same thing would happen.

Gradually the frequency with which I'd get a non start increased and
unplugging from the mains didnt always re-set it.

Anyway the shop changed the p/s without fuss.

Then all was well again with no startup errors for about 9mths until it
started to happen again.

I'm now on my third exchanged power supply and its been working fine for the
past few months - although I'm expecting the same thing to happen later in
the year.

So is this just a crap PS? I cant see how anything in my fairly standard
system could overtax a 550w supply.

Has anyone else experienced this type of thing?

Thanks for any info

Ian
 
Ian Roberts said:
Hi

I'm now on my 3rd power supply.

I bought a £75 550w p/s from a well know high street component supplier.
Click to expand...

What brand and model of PS?
 
Based upon the specs they have provided ... well, what
specs? They don't claim this power supply does anything that
power supplies must do even 30 years ago. What they call
specifications is really nothing more than subjective sales
brochure material. Common symptom among supplies that are
missing essential functions.

Now to move on to what is failing in that supply. Without
numbers, no one can really answer your questions. The
manufacturer makes no claims to provide essential functions.
And you must take a full two minutes to collect numbers - both
when the supply is working and what changes when the supply
fails. Most important numbers for your situation would be
3.3, 5, 12, 5VSB, Power On, and Power Good voltages both
before and after power is turned on. What those signals mean
and where / how to get the associated numbers is in two
previous discussions: "Computer doesnt start at all" in
alt.comp.hardware on 10 Jan 2004 at
http://tinyurl.com/2t69q and
"I think my power supply is dead" in alt.comp.hardware on 5
Feb 2004 at
http://www.tinyurl.com/2musa

With those numbers provides, then those who really
understand how power supplies work can provide useful incite
and possible solutions.

But again, with no specs, the standard response is, "What are
they hiding?"
 
w_tom said:
Based upon the specs they have provided ... well, what
specs? They don't claim this power supply does anything that
power supplies must do even 30 years ago. What they call
specifications is really nothing more than subjective sales
brochure material. Common symptom among supplies that are
missing essential functions.

Now to move on to what is failing in that supply. Without
numbers, no one can really answer your questions. The
manufacturer makes no claims to provide essential functions.
And you must take a full two minutes to collect numbers - both
when the supply is working and what changes when the supply
fails. Most important numbers for your situation would be
3.3, 5, 12, 5VSB, Power On, and Power Good voltages both
before and after power is turned on. What those signals mean
and where / how to get the associated numbers is in two
previous discussions: "Computer doesnt start at all" in
alt.comp.hardware on 10 Jan 2004 at
http://tinyurl.com/2t69q and
"I think my power supply is dead" in alt.comp.hardware on 5
Feb 2004 at
http://www.tinyurl.com/2musa

With those numbers provides, then those who really
understand how power supplies work can provide useful incite
and possible solutions.

But again, with no specs, the standard response is, "What are
they hiding?"
Click to expand...
Or you could just read the posts here and see what everyone else has to say
about QTec PSU's..

SteveH
 
Ian said:
I'm now on my 3rd power supply.

I bought a £75 550w p/s from a well know high street component supplier.

Its a QTEC 13025
Click to expand...
I cant see how anything in my fairly standard system could
overtax a 550w supply.
Click to expand...

What happened when you tested it with a 550W PSU? The Q-tec 550W isn't
one, and this look inside shows that it's built more like a typical
200-250W PSU: www.bit-tech.net/images/review/123/7.jpg

http://takaman.jp has a power needs calculator that's better than most,
but even its estimates are very conservative, and very few computers
actually draw more than 300W.

Can you find a
Fortron/Sparkle/Powerman/PowerQ/Powertech/Trend/Aopen/Hi-Q PSU,
something with a model no. that starts with "FSP" (some start with
"ATX", but so do models of some other brands)? They're really good but
are cheaper than other top quality PSUs. What brand PSUs are available
to you?
 
Ian said:
Hi

I'm now on my 3rd power supply.

I bought a £75 550w p/s from a well know high street component supplier.
Click to expand...

When the third one goes bad or sooner, ask your supplier for a trade-in
toward a good name-brand PS.
 
Matt said:
When the third one goes bad or sooner, ask your supplier for a trade-in
toward a good name-brand PS.
Click to expand...

Sound slike his supplier is charging about twice market rate. Perhaps he
should find a different supplier with better quality PSUs and prices.

--
spammage trappage: replace fishies_ with yahoo

I'm going to die rather sooner than I'd like. I tried to protect my
neighbours from crime, and became the victim of it. Complications in
hospital following this resulted in a serious illness. I now need a bone
marrow transplant. Many people around the world are waiting for a marrow
transplant, too. Please volunteer to be a marrow donor:
http://www.abmdr.org.au/
http://www.marrow.org/
 
Michael said:
Review of 550W PSU:- QTEC 13025 http://www.bit-tech.net/review/123/
Mike.
Click to expand...

No offense but that is a horribly uninformed reviewer. In the first place,
excusing deceptive ratings with "since the majority of PSU manufacturers
use a similar method" is misleading. That should read "since most
'el-cheapo Chinese' PSU manufacturers use a similar method." But the fact
that 'el-cheapo Chinese' PSUs are flooding the market and, hence, appear to
be "the majority" doesn't excuse, nor validate, the deceptive practice of
slapping a number on the thing that is based on meaningless 'peak power'
mumbo jumbo. (anyone care to guess how long, or under what conditions, that
'peak power' can be achieved and of what use it supposedly is? Because
there's no specification for it.)

The reviewer also assumes he can simply add up the 3.3 and 5 volt power for
a combined capability but there is no spec saying that is so and it usually
isn't. So his statement "I calculate the 3.3/5V rails combined should be
able to deliver well over 200W max" has no basis in fact or specification.

The current ratings on the label put it just about par with a medium range
300W PSU, assuming one can trust label numbers by someone who also slaps
"PSU 550W" on a 300W PSU.

Lets compare what the reviewer calls "quite muscular" to something
resembling a 'real' 550W PSU, the Antec TruePower 550 (since the post was
in reply to one mentioning Antec).

Power Qtec Antec
Rail Max Max

3.3V 20A 32A
5V 35A 40A
12V 14 30A

Quite a difference, eh?

Now, if you think getting 300 watts from something labeled 550 watts is a
'good deal', not to mention "muscular" and "beefy," then less power to you,
pun intended.

Lastly, the OP's problem has been 2 failures, in short order, and he's on
his third unit of the same model. Point being, where's the temperature and
MTBF spec on this bogus '550w' PSU? Not to mention that simply because
that reviewer managed to keep one running long enough to power his system
doesn't mean it would last any longer than our OP's PSUs. However, he does
note "I have seen bigger heatsinks on lesser rated PSU's which does make me
wonder about long term reliability."

Oh, as for the Antec:

Operating Temp.
10 to 50ºC

MTBF
80,000 hrs. @ 25ºC

Approvals
UL, TUV, CB, VDE, FCC CLASS B, DEMKO, NEMKO, SEMKO, FIMKO
 
Ian Roberts said:
Hi

I'm now on my 3rd power supply.

I bought a £75 550w p/s from a well know high street component supplier.

Everything worked fine for ages but I then found every so often when I
pressed the on button the lights would come on for a second as if its
about to startup and then nothing - dead as a dodo.

The only way I could get it to start was to disconnect from the mains for
a few seconds, plug it back in and then try again. It would work OK for
the next few start ups and then the same thing would happen.

Gradually the frequency with which I'd get a non start increased and
unplugging from the mains didnt always re-set it.

Anyway the shop changed the p/s without fuss.

Then all was well again with no startup errors for about 9mths until it
started to happen again.

I'm now on my third exchanged power supply and its been working fine for
the past few months - although I'm expecting the same thing to happen
later in the year.

So is this just a crap PS? I cant see how anything in my fairly standard
system could overtax a 550w supply.

Has anyone else experienced this type of thing?

Thanks for any info

Ian
Click to expand...


Hi Guys

Thanks to all of your for replying and enlightening me that this P/S really
is a piece of xxxx for powering a half decent system!

To rub salt into the wound a few weeks after I bought mine it was on sale
for almost half price!

Anyway, the shop has never given me a hard time about swapping it for a new
one - even though I couldnt find my original receipt! However next time the
P/S goes belly up I'll ask to swap it for something better and pay the
extra. I think they also do Enermax supplies so cant go wrong there!

Thanks again

Ian
 
Ian said:
Thanks to all of your for replying and enlightening me that this P/S really
is a piece of xxxx for powering a half decent system!

To rub salt into the wound a few weeks after I bought mine it was on sale
for almost half price!

Anyway, the shop has never given me a hard time about swapping it for a new
one - even though I couldnt find my original receipt! However next time the
P/S goes belly up I'll ask to swap it for something better and pay the
extra. I think they also do Enermax supplies so cant go wrong there!
Click to expand...

I don't know much about the possibility that your PS will damage your
other components the next time it fails. I understand that that happens
sometimes---not necessarily with your Qtec model. You might want to
look into that and consider a replacement before the current one fails.
 
Take from this experience an important lesson. Those power
supplies with a better reputation also provide far more
numerical specifications. Your supply had zero specs; it was
that bad. Lesson applies to other components as well - not
just power supplies. Even with heatsinks. If they don't
provide the all so essential 'degree C per watt' number, then
just like that power supply, assume the worst. No specs is a
major symptom of dumping inferior component at greater profit
to the manufacturer.

Numeric specs don't guarantee minimally sufficient quality.
But no numeric specs is an accurate benchmark for inferior
components.

Why could they sell that power supply so cheaply? Forget to
include essential functions. Higher price does not guarantee
quality. But power supply selling at less then Antec, et al
prices is a sure bet to be missing essential functions.

One function often 'forgotten' protects motherboard, disk,
et al from being damaged by that power supply. Computer
assemblers who don't have basic electrical knowledge would
never know this. But such supplies must then forget to
include numerical specifications.
 
David said:
The reviewer also assumes he can simply add up the 3.3 and 5 volt power for
a combined capability but there is no spec saying that is so and it usually
isn't. So his statement "I calculate the 3.3/5V rails combined should be
able to deliver well over 200W max" has no basis in fact or specification.

Lets compare what the reviewer calls "quite muscular" to something
resembling a 'real' 550W PSU, the Antec TruePower 550 (since the post was
in reply to one mentioning Antec).

Power Qtec Antec
Rail Max Max

3.3V 20A 32A
5V 35A 40A
12V 14 30A

Quite a difference, eh?
Click to expand...

How do they get 550W when those amps x volts add up to much less? Even
generously adding another 50W for the minus and standby voltages
doesn't bring it up enough, so maybe it's the gold plating that makes
the difference.
 
Norm said:
David Maynard wrote:



power for



How do they get 550W when those amps x volts add up to much less? Even
generously adding another 50W for the minus and standby voltages
doesn't bring it up enough, so maybe it's the gold plating that makes
the difference.
Click to expand...

They also put a "peak" rating on each rail and those add up to about 550. I
didn't include those in the table because, without something defining what
their version of 'peak' means, they're meaningless.

For example, I can rate a 1 uF capacitor as 550 'peak' watts because I can
get that out of it for, oh, maybe a fraction of a pico second. Make it a
1000 uF capacitor and I can up that to 550W for maybe a fraction of a nano
second. Now that might be for just once. Or once per minute. Or once per
hour. But just '550W peak' doesn't mean anything (useful).

It's a spec game not unlike the absurd power rating on el-cheapo computer
speakers. As in a ridiculous 280W rating on 3x2 inch cone 7 buck speakers.

There always *is* some obtuse and entirely useless condition the rating is
based on, such as "peak power" or, in the case of the speakers, "PMPO", but
it's similar to rating an automobile at 300 miles per gallon, if you put it
in neutral and roll downhill by gravity. So, to sound terribly 'technical',
you invent a term like MPG-GN (M)iles per (G)allon (G)ravity (N)eutral, so
that it isn't entirely obvious and will hopefully bedazzle the uninformed,
and 'rate' it that way. Then you drop the -GN on the model number, but put
it on the 'spec label' in some obscure location where no one will see it
till after they've bought it, because, well, a "model number" isn't a spec
and this will lead the unsuspecting buyer to think it's the 'real thing',
throw in a suggestive name, and the car becomes a "MileMaster 300MPG."

E.g. "Q-TEC 550Watt Dual Fan Gold PSU" and "Power Magic HP-2100 Black 280W
Amplified Speaker"

The Far East has always been notorious for this sort of thing.
 
you invent a term like MPG-GN (M)iles per (G)allon (G)ravity (N)eutral, so

I get much higher than that with my equipped MGP-GN-IO engine.......only its
hard to steer
 
JAD said:
you invent a term like MPG-GN (M)iles per (G)allon (G)ravity (N)eutral, so

I get much higher than that with my equipped MGP-GN-IO engine.......only its
hard to steer
Click to expand...

Oh YEAAAAaaaaaa? Well, I didn't tell you what gravity constant I based it
on nor the incline of the hill ;)
 
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