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"Ken" <> wrote in message
news:...
> I've been looking at a PC Co. box, it freezes randomly, even when in the
BIOS
> setup - croaking board or suspect PSU? It's an Athlon 1800, and it has a
250
> watt PSU in it. Should I try a new PSU before biffing the board? It's only
> recently started to freeze. The system is a little over 2 years old.


Ken

If the capacitors on the board look ok (no bulging or brown goo) disconnect
all the drives, pull all cards except the video.

Start the system and:

Check the CPU fan is running at the right speed and the heatsink is seated
correctly.


Then check the following (not in any particular order, disconnect the 230v
AC as appropriate)

Power supply fan running.
Power supply voltages OK, suitable meter from DSE at $9.95 (UT20B)
Substitute the Ram, if you have two sticks try each one alternately.
CMOS Battery voltage.
Enter the Bios and check any Temperature readings available.
Reset the bios to default, then performance (optimum, what ever it says)
Substitute the video card.
Reseat the CPU by removing the heatsink and opening the Zip lever &
reclosing. This will upset the thermal interface with the heatsink so have
some suitable heatsink paste available.
Reseat the CMOS chip. (getting desperate now)

If it is still playing up try the CPU/Ram in another MB

If it settles down reintroduce the previously removed drives/cards till you
find the culprit.

About the only other thing to consider is the noise on the power supply
lines.
I had a machine in here recently that had 'perfect' voltages (5, 12, 3.3
etc)
It was flakey starting and ran like a dog when it did, in particular the
burner wouldn't even read a pressed CD.
Had a look with an oscilloscope at the +5 and +12 going to the Burner, 350mv
of noise (0.35v) which is nearly 3 times what is acceptable for a lot of
burners. I did experiment with 470 uf of capacitance at the burners power
socket, they worked ok then.
In the end it required a new power supply as the 3.3v was bad as well.

Cheers
Paul

In article <>, Ken <> wrote:
>I've been looking at a PC Co. box, it freezes randomly, even when in the BIOS
>setup - croaking board or suspect PSU? It's an Athlon 1800, and it has a 250
>watt PSU in it. Should I try a new PSU before biffing the board? It's only
>recently started to freeze. The system is a little over 2 years old.
>

It will have faulty capacitors on the motherboard.
HAVE A LOOK, SOME MAY BE BULGING.
Ive replaced several PC Co boards with this fault.
Is it a red/purple color m/b??

>
>Ken
>
>If the capacitors on the board look ok (no bulging or brown goo) disconnect
>all the drives, pull all cards except the video.
>

Even if all the caps LOOK ok they may still be faulty.
Alot of m/b of that vvintage had cap issues (just a matter of time before they
fail). Symptoms are freezing, not allways turning on etc, general instabity,
bangs when the cap explodes(rarer)
Try RAM,PSU,new vid card, remove all unneeded cables
& cards. Try just 1 stick of RAM.
Also check the CPU/PSU fans are ALLWAYS running ( may be intermittent)

DSE have a MSI (Nforce) m/b on sale for $90, they may be able to get one in
for you.

On Wed, 14 Jul 2004 10:38:12 +1200, Ken <> wrote:

>I've been looking at a PC Co. box, it freezes randomly, even when in the BIOS
>setup - croaking board or suspect PSU? It's an Athlon 1800, and it has a 250
>watt PSU in it. Should I try a new PSU before biffing the board? It's only
>recently started to freeze. The system is a little over 2 years old.

Hi there.

It's definately worth trying another PSU, RAM etc if you have them
available.

That having said, however, I'd almost put money on it being the MoBo.
We see several faulty PC Co machines a week (probably 5-10 on
average), and it is almost always the motherboard (other than the odd
Hyena power supply that have blown up - literally).

Unfortunately our friends at the PC Co appear to have used the
absolutely cheapest components they could get their hands on. Their
prices seemed cheap, but it's the usual story of paying for what you
get.

In article <cd2fu4$sv1$>, says...
> GraB <> wrote in
> news::
>
> > On Wed, 14 Jul 2004 13:14:05 +1200, Ken <> wrote:
> >>Yeah, it's Elitegroup (one and the same?), and the PSU is from
> >>Herolchi Electronic Co.
> >>
> >>I'll test each stick of RAM, then try another PSU.
> >>
> > I am using the same PSU. It is my impression that they are a good
> > one. PC Company used them on all their PC, even the ones running the
> > hottest Athlons and G-Force 4 and CD burners.
>
> Regardless of brand a 250W PSU is bound to be at the bottom end of their
> range and made with the cheapest components. Many brands will make a PSU
> to sell to OEMs that want to save every dollar they can.

Yes and they are usually rated 90 / 110 W.


250 W is perfectly adequate for a lot of uses.

Patrick Dunford <> wrote in
news:. nz:

> In article <cd2fu4$sv1$>,
> says...
>> Regardless of brand a 250W PSU is bound to be at the bottom end of
>> their range and made with the cheapest components. Many brands will
>> make a PSU to sell to OEMs that want to save every dollar they can.
>
> Yes and they are usually rated 90 / 110 W.

Not from what I’ve seen! I have seen some small form factor PSUs that are
rated that low, but in standard ATX size PSUs I have seen nothing under
200W. From Hyena I have seen nothing under 235W, I can get a 300W with
ball bearing fan for $33 incl.

250W should be enough for a basic PC, but if that PSU has a wholesale price
of $20 then I would wonder if there might be some rather marginal
components inside. A good quality 250W PSU that could deliver its rated
output 24/7 for years would not be a problem.


--
Mark Heyes (New Zealand)
See my pics at http://homepages.ihug.co.nz/~markh/
"There are 10 types of people, those that
understand binary and those that don't"

On Wed, 14 Jul 2004 07:50:40 GMT, (Steve Robertson) wrote:

>In article <>, Ken <> wrote:
>>I've been looking at a PC Co. box, it freezes randomly, even when in the BIOS
>>setup - croaking board or suspect PSU? It's an Athlon 1800, and it has a 250
>>watt PSU in it. Should I try a new PSU before biffing the board? It's only
>>recently started to freeze. The system is a little over 2 years old.
>>
>
>It will have faulty capacitors on the motherboard.
>HAVE A LOOK, SOME MAY BE BULGING.
>Ive replaced several PC Co boards with this fault.
>Is it a red/purple color m/b??

It's a purple coloured board. K7VTA3/KT333. No sign of bulging caps, all look
ok. Tried different sticks of RAM, still locks. This was after several hours of
being switched off - the temp in the bios didn't get a chance to go over 30deg,
so I don't think it's overheating. Rebooted, went into bios and left it idling
for a few mins and it locked up again. Tried a different graphics card, same
problem. Will try another PSU tomorrow.

Update: A new 350w PSU seems to be doing the job, running for 2hrs no problems.
Just running Prime Torture Test on it now.

Thanks for everyones ideas

In article <cd3cat$j73$>, says...
> Patrick Dunford <> wrote in
> news:. nz:
>
> > In article <cd2fu4$sv1$>,
> > says...
> >> Regardless of brand a 250W PSU is bound to be at the bottom end of
> >> their range and made with the cheapest components. Many brands will
> >> make a PSU to sell to OEMs that want to save every dollar they can.
> >
> > Yes and they are usually rated 90 / 110 W.
>
> Not from what I=3Fve seen! I have seen some small form factor PSUs that are
> rated that low, but in standard ATX size PSUs I have seen nothing under
> 200W. From Hyena I have seen nothing under 235W, I can get a 300W with
> ball bearing fan for $33 incl.

I've seen quite a few standard ATX cases (mini tower) fitted with 110W
PSU. The PSU fits into a standard ATX case on the same hole spacings etc.
The actual size of the PSU case is irrelevant if it fits into a standard
ATX case. PSU cases come in all different sizes.

In article <cd3cat$j73$>, says...
> Patrick Dunford <> wrote in
> news:. nz:
>
> > In article <cd2fu4$sv1$>,
> > says...
> >> Regardless of brand a 250W PSU is bound to be at the bottom end of
> >> their range and made with the cheapest components. Many brands will
> >> make a PSU to sell to OEMs that want to save every dollar they can.
> >
> > Yes and they are usually rated 90 / 110 W.
>
> Not from what I=3Fve seen! I have seen some small form factor PSUs that are
> rated that low, but in standard ATX size PSUs I have seen nothing under
> 200W.

THere is no "standard ATX size PSU". They are all different sizes.

There is a standard ATX PSU in terms of fitting the standard ATX cases.

I have seen 110W and 145W ATX PSUs fitted into generic Chenbro ATX
minitower cases. A 250W PSU fits easily in the same case.

Patrick Dunford <> wrote in
news:. nz:

> I have seen 110W and 145W ATX PSUs fitted into generic Chenbro ATX
> minitower cases. A 250W PSU fits easily in the same case.

OK, this may well be true.

BUT
If a PSU manufacturer doesn’t make less than a 250W in THEIR standard
range, then there is a good chance that their 250W is their cheapo standard
PSU that they sell to budget OEMs.

My experience is that the 250W PSUs are made cheaper than the higher rated
ones. i.e. fans not ball bearing, cheaper design on fan grill, lighter
flimsier feeling PSU, etc. Some 300W PSUs are also very cheap, good for
advertising 300W while not advertising that it is crap. Some 300W PSUs are
quite good and noticeably dearer.

My personal observations lead me to believe that generally PSUs under 300W
and the cheap 300W ones are built to a tight budget. The dearer 300W PSUs
and higher rated ones are generally built more towards performance than
budget. Of course there will be exceptions to this but the lower the price
the more likely the PSU is cheaply made.


--
Mark Heyes (New Zealand)
See my pics at http://homepages.ihug.co.nz/~markh/
"There are 10 types of people, those that
understand binary and those that don't"