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Author Topic: 360 Mosfet Blown. Wont Turn On.  (Read 26 times)

mr sambo

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360 Mosfet Blown. Wont Turn On.
« on: September 03, 2010, 07:00:00 AM »
(IMG:http://img69.imageshack.us/img69/500/360ca.jpg)

First sorry for crappy picture, but it does its job  (IMG:style_emoticons/default/tongue.gif) .
Mosfet shown in picture is in horrible condition and is missing one leg  (IMG:style_emoticons/default/dry.gif)  .
When mobo is connected to PSU, motherboard wont turn on and PSU-led stays orange.
Motherboard has had incorrect extra fan installation, which made the PSU to show red when pressing powerbutton.

Requesting tips on how to take out the mosfet cleanly, and what kind of part to use as replacement.
Other tips in getting this box working again are also welcome   (IMG:style_emoticons/default/happy.gif) .

Thanks in advance.
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MadMaxGR

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360 Mosfet Blown. Wont Turn On.
« Reply #1 on: September 03, 2010, 07:15:00 AM »
You need the exact part to replace this one. You can't just take it off and live without it. You need a good hot soldering iron, solder paste and some soldering lead. Heat up the soldering, melt some lead on the factory lead on the MOSFET legs, use some paste on it and desolder! You need some soldering skills, as you understand. Enjoy the adventure (IMG:style_emoticons/default/smile.gif)
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mr sambo

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360 Mosfet Blown. Wont Turn On.
« Reply #2 on: September 03, 2010, 07:25:00 AM »
Problem is, that i don't really know what kind of mosfet it is.
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RDC

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360 Mosfet Blown. Wont Turn On.
« Reply #3 on: September 03, 2010, 08:15:00 AM »
It's the 3.3vsb Regulator. 3.3v Fixed, 1A, Low Drop Out, DPAK.


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mr sambo

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360 Mosfet Blown. Wont Turn On.
« Reply #4 on: September 03, 2010, 09:16:00 AM »
QUOTE(RDC @ Sep 3 2010, 03:15 PM) *

It's the 3.3vsb Regulator. 3.3v Fixed, 1A, Low Drop Out, DPAK.


Thank you, i'll visit the local electronics shop asap  (IMG:style_emoticons/default/smile.gif) .
Maybe i should check all the standby voltages after replacing the mosfet(?).
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RDC

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360 Mosfet Blown. Wont Turn On.
« Reply #5 on: September 03, 2010, 09:28:00 AM »
I'd be surprised if that fixes it, as it's kinda rare for a Regulator to fry like that in a 360, and since it powers the Southbridge if someone shot more voltage down that line it could be fried as well.
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mr sambo

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360 Mosfet Blown. Wont Turn On.
« Reply #6 on: September 03, 2010, 12:42:00 PM »
QUOTE(RDC @ Sep 3 2010, 04:28 PM) *

I'd be surprised if that fixes it, as it's kinda rare for a Regulator to fry like that in a 360, and since it powers the Southbridge if someone shot more voltage down that line it could be fried as well.


It hasn't blown like that.. Looks more like inexperienced soldering that
has caused serious damage..  (IMG:style_emoticons/default/rolleyes.gif)

Seems almost like the extra fan "install" took place here. I'll post results when i get to it.
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