Re: P3b-f won't boot,strange beep code help...please?

jcazz wrote:
RobV wrote:
jcazz wrote:

[snip]


Thanks for your input Rob,
I cleaned the system thoroughly and found an insect stuck in my
video card fan. Now Bios is reporting 5V leg sometimes fluctuates
between 4.3-4.9. I think this is my problem now. The mobo light
sometimes
blinks then crashes. Could the fan on the graphics cause the
fluctuation? IS this the PSU or mobo failure? I have a volt meter,
how do I check 5v leg on psu?
Thanks again
John

Ah, the old insect in the fan problem, eh? ;-)

Checking the voltage is easy with the link Andre gave for the ATX
plug. However, he did get the +5V and +12V colors reversed. Yellow
is +12V and red is +5V, with black being ground, of course. You can
measure the voltage anywhere there is access to the red and yellow
wires. You can get ground anywhere you can get to a black wire.

Yes, the fluctuation is bad, and is going way lower than tolerance
would allow. You may have a bad power supply, and/or bad
capacitors: the big electrolytic capacitors near and around the CPU.
If you see any kind of bulging on top of, or the sides of the caps,
and/or light brown colored crud on top of, or the bottom of any of
the caps, then they are bad and need replacing.


Rob,

Yes... The old fly in the fan gag... the oldest one in the Asus book!
Now I know the beep codes for it.

However, I did notice that the ATX PSU supply plug did have some brown
scorch marks on it on the outside of the plastic. I don't know exactly
which pins but believe it was around 21 or 22, looks like the 5v line.
Could this mean the plug is making poor contact with mobo and thus
reason for restart? I'll have to investigate further.

Yes, those are +5V lines, and the signs of burning would indicate that
there is a problem with the ATX connector. Since these are very high
current lines, a poor connection can cause heat and oxidation of the
plug and socket pins. To the best of your ability, clean the plug and
socket pins and make sure they fit tight into the ATX socket. This is
probably where the problems you are having lies.

Second... after complete tear down and rebuild last night (including
opening PSU and cleaning) the machine ran great for over an hour on
the bench. Multiple times I shut down and restarted and even ran a
video without a problem. When I returned it to the house the computer
run fine until I went on the internet. Maybe it's coincidence but
most crashes occur on internet. I have another PSU but it only has
plugs for 4 drives. Third... When the system was running in house
the sound card would seem to power intermittently. I could hear it
powering up and off. XP
showed it in the device MGR as OK but never got sound.

I built this PC when P3B-f was first released and it has run flawless
for years. I once had a 300mhz running at 450 and never had CPU temp
above 87 F. Since I installed Win XP it has been nothing but problems.
I know it's time for a new machine but waiting for prices on DDR-3 to
fall and Asus to work bugs out of P5K series.

Besides the ATX connector, look at the capacitors as I mentioned.

Thanks again for your help... any further comments, suggestions are
appreciated.

John

You're welcome, and good luck with whatever you decide to do.


.

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