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Old 01-20-2015, 09:07 AM   #11
selldoor
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Join Date: Dec 2010
City & State: Lancashire UK
Posts: 7,865
Default Re: Asrock H61M-GS no power

Quote:
Originally Posted by c_hegge View Post
One thing I have noticed there is that your CMOS battery is installed backwards. That - may - be part of the problem.
Good Spot that .


Quote:
Originally Posted by Rippergr
I checked some of the mosfets in the 4th picture and in some I have resistance(buzzer) in two pins and in some only on the head . Is this normal
You should give result in ohms Bad is usually less than 30ohms but it would still buzz
Mosfets
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If you have a manual range multimeter, set it to 200 ohms (two hundred). You can test a mosfet (Q, IC designation) "in circuit" by (power off and unplugged)

a) black on pin 1- red on pin 2 - record ohms
b) black on pin 1- red on pin 3 - record ohms
c) black on pin 2- red on pin 3 - record ohms

If any ohm reading is less than 30 ohm you might have shorted mosfet. Remove from circuit and repeat the tests to verify.

Some mosfets are more than 3 pins. To test those, identify the part number and search for its datasheet. Once you find the datasheet, the pins will be designated source (S), gate (G), and drain (D). It will probably be documented as S1, S2, G1, G2, D1, D2.

Simply test

a) black on pin S1- red on pin G1 - record ohms
b) black on pin S1- red on pin D1 - record ohms
c) black on pin G1- red on pin D1 - record ohms

Repeat for the "2" pins. That is S2-G2, S2-D2, G2-D2.
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