"N Alley" said:
New ASUS KAN-E with AMD 64 30000
Just put together and when I push and release the power button fans stop
turning and PC won't power on. If I hold the button in fans will turn for x
amount of seconds then stop.
I'm using a new Liteon case with a suncheer 400w ps.
Any help would be appreciated
1) Check the label on the power supply. Does the +12V have at
least a 15 amp rating ? If it is rated for 10 amps, that might
barely be enough to get it to work. Athlon64 and P4 systems
draw processor current from +12V, and 15 amps is a good basic
system current rating. AthlonXP (Barton etc) systems draw
current for the processor from +5V, and 20 or 25 amps on
+5V would help with those. The rails other than the one the
processor is using aren't quite as critical. Most power supplies
can easily meet those secondary load requirements (at least
on a single processor desktop system - a server is different).
When you turn on the PSU, does the green LED light on the
motherboard glow ? And, when you push the power button on
the front of the case, does the green LED remain lit ? The
green LED should not blink and the +5VSB on the power supply,
that powers the LED, should never wink out, even for a second,
because if the +5VSB fails for a short interval, the rest
of the power supply will shut off. +5VSB runs the supervisor
circuits on the motherboard, the green motherboard LED,
and the control circuits on the power supply.
Of parts in a computer, the power supply is the weakest link.
No matter what brand you buy, failures abound. One measure
of quality, is the physical weight of a power supply, as there
is a web page where someone studied the weight of power supplies
and how well they work. You cannot expect miracles from bargain
power supplies.
I like to test power supplies before using them, but the
amount of effort required to find loading resistors and
build a wire harness for a load tester, is more than the
average home builder would want to do. The resistors draw
enough current, that I keep a fan, also powered by the PSU
under test, blowing over the resistors to keep them cool.
With the resistors connected, I measure the voltage on the
rails, and let the unit run for a few hours, just to be safe.
(I don't attempt to run the PSU at full power, just a light
load, to prove it isn't a complete dud.)
2) Check that the heatsink is properly installed on the processor.
It could be that if the CPU fan isn't connected to the CPU fan
header, that the motherboard is shutting down. Either it is
going over temperature or the BIOS thinks the fan is not turning.
3) Your motherboard has Voice POST (Vocal POST). Connect amplified
speakers to the lime colored, Lineout connector on the back of
the computer. The error messages come out on this jack, no matter
whether you are using a third party sound card or not. Listen
for an error message through your amplified speakers when you
try to start the computer. To work, the Voice POST does not need
any components installed on the board. You can, in fact, use
just the motherboard, the PSU, and touch a screwdriver tip to
the two pins where the POWER switch plugs into the PANEL header,
to turn on the system. The Voice POST will report the CPU is not
there. Then, you can install the CPU and heatsink/fan, and start
the system again. This time, the error message should be
reporting "failed memory test" or the like. If it says failed
CPU test, then it is more likely that the CPU is defective or
the voltage feeding the CPU is weak.
The Voice POST runs from +5VSB, and if it refuses to say
anything, that means the reset signal could be stuck. And,
that in turn, could be caused by some voltage generated on
the motherboard not being correct. I think reset is released,
when all voltages are within spec.
The best way to do this kind of pre-install testing, is outside
the case. I like to use a big thick book and some cardboard, to
support the motherboard. Remove the PSU from the case and plug
it into the motherboard. Then, it is easy to use a screwdriver
tip, to touch the two pins on the PANEL header, to turn on the
system. Only a momentary contact with the pins is necessary.
Be careful to only touch those two pins with the screwdriver tip.
Because the voice messages are heavily compressed, you'll need
to flip the manual open to section 3.3 in the manual, and compare
the Voice messages to the list of error messages in the manual.
If you find any more symptoms to the problem, don't hesitate to
post them. Our specialty here, is guessing
HTH,
Paul
