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SOT-23 Transistor ''750'' marking?

AFex54

Apr 10, 2015
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I looked thoroughly and couldnt find what part this is. there was only a couple SOT23 part codes online that even contained ''750'' and they are diodes.

There are a large number of them located in the power supply input area of a graphics card for a computer.
 

Harald Kapp

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Nov 17, 2011
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Photo?
How sure are you this is a transistor, not a diode?
 

AFex54

Apr 10, 2015
144
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Here are the photos. On one side they are beside a couple of AON7403 MOSFETS, a small amount of water got on this area and I want to replace the mosfets and 750 transistors here to see if it fixes the issue.

There a 2 power inputs on this graphics card, the card powers up and gives ''no external power'' error with no power inputs, it also boots up with only the right connector with a ''connect other power'' error.
Only with the left side power connector does the card fail to boot up, the lights only flashing on for a second.
Since its a multilayered PCB Its hard to tell by the traces what the left power connector is actually powering that's causing the issue but it definitely looks like it might be these MOSFETS and 750 Ts, which is exactly where the water was.
Its was a very expensive graphics card, its a worth a shot at least

IMG_1429.JPG IMG_1430.JPG
 
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