Things to try if you turn on the pc's power and nothing
happens i.e. power supply unit (PSU) fan not running , no sound , no display and
no hard disk activity.
This assumes that you have power to your
system.Try the following guideline checks (at your own risk ,the author will
not be held responsible for damage caused).
Press the case power switch ,if the PSU fan does not starup
then check
- Has the power switch lead fell off the motherboard
connection in transit .refit if necessary.
- Check case switch by carefully removing connector from
motherboard and shorting out the two pins on the board , the PSU fan should
start-up if the switch was the problem.
- the system PSU will not start-up if there is a short on any
drive in the system or if there is a problem with the motherboard. LEAVE
motherboard power lead connected and disconnect all other drives and turn
on.If the PSU fan starts then one of the drives you disconnected is at fault .
Reconnect power to each drive in turn trying the system each time.This will
pinpoint which component is at fault.
- If the PSU fan fails to start ,then the problem is either
with the motherboard or the PSU itself.To check which it is ,there is a test
lead available that plugs into the ATX motherboard supply lead which will
allow the power supply unit fan to run and a led light on the test led to work
if the PSU is O.k. when power is supplied to it..If the fan does not run and
the led does not light then the PSU is at fault and should be replaced.
- If the PSU is proven to be o.k. then the problem is the
motherboard either the board itself or something plugged into it.Disconnect
all connectors from motherboard EXCEPT power supply lead and turn on case fan
switch .remove all addin pci cards.See if the PSU fan starts now.If it does
not start it is the motherboard or system memory.
Try a known good memory module.If it still doesn't work you
need a new main board.(a good time to upgrade)
Please note that you MUST NOT try to start-up a PSU
without a motherboard or test lead connected to it !!
If you are not confident in the tasks listed then leave it to
the expert !!
© Homepcnovice 2010 All rights Reserved.
Revised:
July 07, 2008