Marginal OEM Power Supply

Last summer I bought a box from a very big OEM at a good price.

The box would not boot on delivery because the RAM had been installed
incorrectly, so it's clear that, if the box was tested, it was tested
before the RAM was installed, and now I'm wondering at what stage of
assembly the boxes are supposedly tested (not at all after assembly?).

I increased the memory by 50%, reinstalled the incorrectly installed
memory, and added a second HDD, and the machine did boot.

I haven't used the machine much, and, in particular, I haven't used the
video much, but this summer I started encountering video problems while
trying to upgrade Fedora.

Since I had an extra video card available, I tried changing video card.
My replacement video card drew too much power and the machine would
not even boot. The easy conclusion was that the power supply was either
malfunctioning or marginal to begin with.

The computer store is a fair drive, so I bought both a replacement power
supply and a very low end video card. I don't like replacing power
supplies, so I tried the video card. Works like magic. I'll replace
the power supply if I get around to it. I mostly run the box remotely
and I don't need fancy video. As far as warranties are concerned, I
can't imagine what circumstances would make a warranty repair worth my
time, so I don't worry about it.

Maybe when you pay for installed upgrades, you pay for an upgraded power
supply. Since the memory was added to this box with no further testing,
it's easy to imagine that boxes might be shipped with upgrades such that
the power supply is often marginal or inadequate.

Anybody have any insight?

Robert.

Robert Myers wrote:
Last summer I bought a box from a very big OEM at a good price.

The box would not boot on delivery because the RAM had been installed
incorrectly, so it's clear that, if the box was tested, it was tested
before the RAM was installed, and now I'm wondering at what stage of
assembly the boxes are supposedly tested (not at all after assembly?).

The stage where the end user tries to boot the box, at least from the vendor you
used.

I increased the memory by 50%, reinstalled the incorrectly installed
memory, and added a second HDD, and the machine did boot.

I haven't used the machine much, and, in particular, I haven't used the
video much, but this summer I started encountering video problems while
trying to upgrade Fedora.

Since I had an extra video card available, I tried changing video card.
My replacement video card drew too much power and the machine would not
even boot. The easy conclusion was that the power supply was either
malfunctioning or marginal to begin with.

That's a fair guess, many are sized to the need as sold. That's not an unfair
practice, just one which should be more obvious before it bites you.

The computer store is a fair drive, so I bought both a replacement power
supply and a very low end video card. I don't like replacing power
supplies, so I tried the video card. Works like magic. I'll replace
the power supply if I get around to it. I mostly run the box remotely
and I don't need fancy video. As far as warranties are concerned, I
can't imagine what circumstances would make a warranty repair worth my
time, so I don't worry about it.

Unless you have some reason to use a brick and mortar store, places like newegg
and tigerdirect are good sources for parts.

Maybe when you pay for installed upgrades, you pay for an upgraded power
supply. Since the memory was added to this box with no further testing,
it's easy to imagine that boxes might be shipped with upgrades such that
the power supply is often marginal or inadequate.

Anybody have any insight?

Except for gamer machines, vendors expect the cover to stay on. The bad memory
install would have gotten a complaint from me, I doubt anyone ships without a
smoke test, at least not anyone remotely reputable. I bet someone saved a bit of
time by not doing it as s/he should.

Bill Davidsen wrote:
Robert Myers wrote:

snip


I increased the memory by 50%, reinstalled the incorrectly installed
memory, and added a second HDD, and the machine did boot.

I haven't used the machine much, and, in particular, I haven't used
the video much, but this summer I started encountering video problems
while trying to upgrade Fedora.

Since I had an extra video card available, I tried changing video
card. My replacement video card drew too much power and the machine
would not even boot. The easy conclusion was that the power supply
was either malfunctioning or marginal to begin with.

That's a fair guess, many are sized to the need as sold. That's not an
unfair practice, just one which should be more obvious before it bites you.

Never occurred to me that they would size the power supply to the actual
sale. That means that, even if you pay outrageous prices for a
subsequent OEM add-on, it might not work. I'd call that deceptive
marketing.

The computer store is a fair drive, so I bought both a replacement
power supply and a very low end video card. I don't like replacing
power supplies, so I tried the video card. Works like magic. I'll
replace the power supply if I get around to it. I mostly run the box
remotely and I don't need fancy video. As far as warranties are
concerned, I can't imagine what circumstances would make a warranty
repair worth my time, so I don't worry about it.

Unless you have some reason to use a brick and mortar store, places like
newegg and tigerdirect are good sources for parts.

A Microcenter is reasonably close, and, if you shop carefully, their
prices are hard to beat.

**And**, if something goes wrong, I know how to find the store manager.

Maybe when you pay for installed upgrades, you pay for an upgraded
power supply. Since the memory was added to this box with no further
testing, it's easy to imagine that boxes might be shipped with
upgrades such that the power supply is often marginal or inadequate.

Anybody have any insight?

Except for gamer machines, vendors expect the cover to stay on. The bad
memory install would have gotten a complaint from me, I doubt anyone
ships without a smoke test, at least not anyone remotely reputable. I
bet someone saved a bit of time by not doing it as s/he should.

The default memory configuration for this machine was two sticks. A
third stick was added to this three-channel machine as an "upgrade."

DIMM slots 0 and 2 had been installed correctly and the "upgrade" was
installed to slot 3.

This purchase was from a *very* well-known OEM. It's really hard to
imagine who, other than someone like me or a gamer, would buy such a
box. The only reason I don't name the company is that I know engineers
who work there.

Robert.

In comp.sys.ibm.pc.hardware.chips Robert Myers wrote in part:
Never occurred to me that they would size the power supply
to the actual sale. That means that, even if you pay
outrageous prices for a subsequent OEM add-on, it might
not work. I'd call that deceptive marketing.

It might well be. Perhaps this was a batch of computers
specifically built for some megacorp refresh but which proved
out to have a high defect rate -- either as RAM installation
or PSU quality. It was subsequently rejected and dumped on
the resale market where you bought it cheaply.

They ought to have been sold as "debranded", but perhaps
someone was asleep at bigOEM. Or a disobedient reseller.

The Shenzhen suicides and subsequent salary doubling
do not indicate high-quality.


-- Robert

Robert Redelmeier wrote:
In comp.sys.ibm.pc.hardware.chips Robert Myers wrote in part:
Never occurred to me that they would size the power supply
to the actual sale. That means that, even if you pay
outrageous prices for a subsequent OEM add-on, it might
not work. I'd call that deceptive marketing.

It might well be. Perhaps this was a batch of computers
specifically built for some megacorp refresh but which proved
out to have a high defect rate -- either as RAM installation
or PSU quality. It was subsequently rejected and dumped on
the resale market where you bought it cheaply.

They ought to have been sold as "debranded", but perhaps
someone was asleep at bigOEM. Or a disobedient reseller.

Not a reseller. Direct purchase from the OEM.

Your thought that my deal might have been the result of a messed up
corporate order would explain some weird things. For example, why would
anyone put two 2Gb memory sticks in a three-channel box to begin with?

The boxes don't make much sense for a big corporate purchase, but maybe
they weren't the right boxes to begin with. The order was for a more
normal corporate machine with 4Gb of memory and a core 2 dual processor.
4Gb was stuck into the wrong boxes and the boxes were tested before
someone said oops. Test the memory, tell your guys to stick it into the
boxes and offer a special deal. Who knows. The extra stick of memory
seems obviously to have been stuck in. Someone who knew to skip slot 1
would also know to skip slot 3.

Robert.

Robert Myers wrote:
Bill Davidsen wrote:
Robert Myers wrote:

snip


I increased the memory by 50%, reinstalled the incorrectly installed
memory, and added a second HDD, and the machine did boot.

I haven't used the machine much, and, in particular, I haven't used
the video much, but this summer I started encountering video problems
while trying to upgrade Fedora.

Since I had an extra video card available, I tried changing video
card. My replacement video card drew too much power and the machine
would not even boot. The easy conclusion was that the power supply
was either malfunctioning or marginal to begin with.

That's a fair guess, many are sized to the need as sold. That's not an
unfair practice, just one which should be more obvious before it bites
you.

Never occurred to me that they would size the power supply to the actual
sale. That means that, even if you pay outrageous prices for a
subsequent OEM add-on, it might not work. I'd call that deceptive
marketing.

The computer store is a fair drive, so I bought both a replacement
power supply and a very low end video card. I don't like replacing
power supplies, so I tried the video card. Works like magic. I'll
replace the power supply if I get around to it. I mostly run the box
remotely and I don't need fancy video. As far as warranties are
concerned, I can't imagine what circumstances would make a warranty
repair worth my time, so I don't worry about it.

Unless you have some reason to use a brick and mortar store, places
like newegg and tigerdirect are good sources for parts.

A Microcenter is reasonably close, and, if you shop carefully, their
prices are hard to beat.

**And**, if something goes wrong, I know how to find the store manager.

That qualifies as a reason for sure, didn't think "reasonably close," since you
earlier said "The computer store is a fair drive," but I know what you mean, not
too far to go to save a shipping cycle but far enough that you don't want to do
it twice.

Maybe when you pay for installed upgrades, you pay for an upgraded
power supply. Since the memory was added to this box with no further
testing, it's easy to imagine that boxes might be shipped with
upgrades such that the power supply is often marginal or inadequate.

Anybody have any insight?

Except for gamer machines, vendors expect the cover to stay on. The
bad memory install would have gotten a complaint from me, I doubt
anyone ships without a smoke test, at least not anyone remotely
reputable. I bet someone saved a bit of time by not doing it as s/he
should.

The default memory configuration for this machine was two sticks. A
third stick was added to this three-channel machine as an "upgrade."

DIMM slots 0 and 2 had been installed correctly and the "upgrade" was
installed to slot 3.

I would expect that to pass smoke test, then, incorrectly installed as in not
full speed rather than upside down or something, I'm actually surprised that it
didn't show up working on POST and only be obvious with the cover off or using
dmidecode. Or whatever the Windows tool is to get the same information.

This purchase was from a *very* well-known OEM. It's really hard to
imagine who, other than someone like me or a gamer, would buy such a
box. The only reason I don't name the company is that I know engineers
who work there.

Robert.

Bill Davidsen wrote:

Robert Myers wrote:

DIMM slots 0 and 2 had been installed correctly and the "upgrade" was
installed to slot 3.

I would expect that to pass smoke test, then, incorrectly installed as
in not full speed rather than upside down or something, I'm actually
surprised that it didn't show up working on POST and only be obvious
with the cover off or using dmidecode. Or whatever the Windows tool is
to get the same information.


I would have expected it to boot, too, but it didn't. I tried to boot
before opening the machine. It's been long enough that I don't remember
if it got past a power-on POST and stopped at a blank screen. Maybe
that would have constituted passing a smoke test. I can understand why
a tester in a hurry wouldn't want to wait for Vista to boot.

Since I intended to add memory, I didn't hesitate to take the cover off
to see what was going on. Making what I thought would be a correct
memory install fixed the problem.

Robert.

On 6/19/2010 1:57 AM, Robert Myers wrote:
The computer store is a fair drive, so I bought both a replacement power
supply and a very low end video card. I don't like replacing power
supplies, so I tried the video card. Works like magic. I'll replace the
power supply if I get around to it. I mostly run the box remotely and I
don't need fancy video. As far as warranties are concerned, I can't
imagine what circumstances would make a warranty repair worth my time,
so I don't worry about it.

Maybe when you pay for installed upgrades, you pay for an upgraded power
supply. Since the memory was added to this box with no further testing,
it's easy to imagine that boxes might be shipped with upgrades such that
the power supply is often marginal or inadequate.

Anybody have any insight?

I can quite imagine that an OEM box would have the bare minimum power
supply specs require. I mean this must be one of several reasons why an
OEM box is cheaper than any box that you can put together yourself. You
probably would buy a PS with a little bit of extra margin in it, and
it's likely that you probably couldn't even buy a PS as low as what's in
an OEM box.

Yousuf Khan

Yousuf Khan wrote:
On 6/19/2010 1:57 AM, Robert Myers wrote:
The computer store is a fair drive, so I bought both a replacement power
supply and a very low end video card. I don't like replacing power
supplies, so I tried the video card. Works like magic. I'll replace the
power supply if I get around to it. I mostly run the box remotely and I
don't need fancy video. As far as warranties are concerned, I can't
imagine what circumstances would make a warranty repair worth my time,
so I don't worry about it.

Maybe when you pay for installed upgrades, you pay for an upgraded power
supply. Since the memory was added to this box with no further testing,
it's easy to imagine that boxes might be shipped with upgrades such that
the power supply is often marginal or inadequate.

Anybody have any insight?

I can quite imagine that an OEM box would have the bare minimum power
supply specs require. I mean this must be one of several reasons why an
OEM box is cheaper than any box that you can put together yourself. You
probably would buy a PS with a little bit of extra margin in it, and
it's likely that you probably couldn't even buy a PS as low as what's in
an OEM box.


I had previously noted the puniness of power supplies on OEM boxes, but
not by overloading them to the point where the machine wouldn't run. I
don't think that upping the RAM by 50% and adding a HDD causing a power
supply overload is a reasonable expectation.

Something else about this machine that is shaved very close is the
thermal design. It will not run for long with the side cover removed.
That wouldn't surprise me if the side cover included a duct, but there
are only holes strategically placed in the side panel. The CPU has an
enormous heat sink, but no fan of its own!

Robert.

In comp.sys.ibm.pc.hardware.chips Robert Myers wrote in part:
I had previously noted the puniness of power supplies on OEM
boxes, but not by overloading them to the point where the machine
wouldn't run. I don't think that upping the RAM by 50% and adding
a HDD causing a power supply overload is a reasonable expectation.

Agreed. HDDs (especially 10k) can cause a heavy motor-start
load on the 12V but should otherwise be fine. One problem with
big OEMs is they are also aiming at EPA EnergyStar targets
which cause them to tight-size PSUs for max efficiency.
The German TuV may also have powerfactor targets.


Something else about this machine that is shaved very close is
the thermal design. It will not run for long with the side cover
removed. That wouldn't surprise me if the side cover included a
duct, but there are only holes strategically placed in the side
panel. The CPU has an enormous heat sink, but no fan of its own!

There is your clue, no CPU fan -- the cover is a duct. With the
cover off, air can bypass the CPU heatsink and slip straight to
[from] the PSU fan. I've built machines without CPU fans, and
you have to be very careful about airflow.


-- Robert R